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  • Kidney  (70)
  • Mouse  (70)
  • Springer  (140)
  • 1970-1974  (140)
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  • Springer  (140)
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 364 (1974), S. 365-369 
    ISSN: 1432-2307
    Keywords: Virus Diseases ; Cytomegalic Inclusion Disease ; Kidney ; Kidney Diseases ; Glomerulonephritis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This paper reviews a case of a newborn child which died soon after birth in consequence of a cytomegalic inclusion disease involving the brain, liver, lungs and kidneys. The interest of the case lies in the unusual finding of lesions of the vascular loops of the renal glomeruli. These lesions were represented by focal areas of homogeneous appearance which were strongly basophilic and PAS-positive. Although the nature of these areas has not been completely established, the renal lesions can be tentatively defined as focal, probably necrotizing glomerulonephritis. The association of this type of glomerular lesions with cytomegalic inclusion disease has not been previously reported.
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  • 2
    ISSN: 1433-8580
    Keywords: Kidney ; Concentrating mechanism ; Corticomedullary gradients ; Protein ; Niere ; Konzentrierung ; Corticomedulläre Gradienten ; Protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wurden die Albumingradienten der Rattenniere und ihre Beeinflussung durch Furosemid und hypertones Mannit nach mehrtägiger Infusion hyperosmolarer Natriumchloridlösungen untersucht. Als Indicator der Eiweißkonzentrationen diente der an Albumin gebundene Farbstoff Evans blue. Es wurde gefunden: 1. Nach mehrtägiger Natriumkonzentrierung (890 mOsm/l, Urinfluß 1,7 ml/Std) beträgt die Gesamtosmolarität im Gewebe der Papillenspitze 1015 ± 181 mOsm/l und im Sammelrohrurin 1059 ± 42 mOsm/l. Der Eiweißgradient nimmt von der Rinde zur Papillenspitze kontinuierlich auf das 4,25fache der Rindenwerte zu. 2. Nach Furosemid (2 × 0,7 mg/100 g KG) fällt die Gesamtosmolarität im Papillenspitzengewebe auf 344 ± 28 mOsm/l und im Sammelrohrurin auf 385 ± 30 mOsm/l ab. Das stündliche Harnvolumen erhöht sich auf 8,2 ± 2,04 ml. Die Albumine werden nur noch um das 1,8fache ihrer Rindenwerte und zu 35% ihrer ursprünglichen Konzentration angereichert. 3. Unter 20%iger Mannitinfusion (Flußgeschwindigkeit 1,5 ml/Std, Infusionszeit 110 min) fällt die Gesamtosmolarität im Papillenspitzengewebe auf 475 ± 84 mOsm pro Liter und im Sammelrohrurin auf 467 ± 51 mOsm/l ab. Das stündliche Harnvolumen wächst auf 6,4 ± 1,96 ml an. Die Albumine werden nur noch um das 2fache ihrer Rindenwerte und zu 42% ihrer Ausgangskonzentration angereichert. Für die Beeinflussung der corticomedullären Eiweißgradienten durch Mannit und Furosemid werden neben Änderungen der rheologischen Eigenschaften der Erythrocyten Volumen- und osmotisches Substanzangebot an die Vasa recta-Schleifen verantwortlich gemacht. Die Funktion dieser Gegenstromgefäße ist von der osmotischen Substanz- und Wasseraufnahme aus den Henleschen Schleifen und Sammelrohren abhängig.
    Notes: Summary Subject of the examinations were the albumin gradients of the tissue of the rat kidney and the influence of hypertonic mannitol and furosemide on it during long-term infusion of hyperosmolar sodium chloride. As an indicator of the protein concentrations Evans blue dye was injected, which binds to albumen. The following results were obtained: 1. After several days' sodium concentration (890 mOsm/l, urine flow 1.7 cc/hr) the total osmolarity in the tissue of the papillary tip is found to be 1015 ± 181 mOsm per litre and in the collecting ducts 1059 ± 42 mOsm/l. The protein gradients rise continuously towards the papillary tip up to 4.25 times of the cortex values. 2. After injection of furosemide (2 × 0.7 mg/100 g b.w.) the total osmolarity in the papillary tissue decreases to 344 ± 28 mOsm/l and in the collecting ducts to 385 ± 30 mOsm/l. The urine volume per hour increases to 8.2 ± 2.04 cc. Albumin is enriched merely to about 1.8 times of the cortex values and to 35% of its former concentration. 3. During the infusion of hypertonic mannitol (flow-rate 1.5 cc/hr, time of infusion 110 min) the total osmolarity of the papillary tissue decreases to 475 ± 84 mOsm/l and in the collecting ducts to 467 ± 51 mOsm/l. The urine volume rises to 6.4 ± 1.96 cc/hr. Albumin is enriched merely to about twice of the cortex values and to 42% of its original concentration. Besides changes of the rheological characteristics of the red cells, volume and osmotic substance supply to the vasa recta are held responsible for the influence of hypertonic mannitol and furosemide on the corticomedullary albumin gradients, while they are administrated. The countercurrent exchange efficiency of the vasa recta is dependent on both the water and osmotic substance uptake out of the loops of Henle and the collecting ducts.
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  • 3
    ISSN: 1433-8580
    Keywords: Kidney ; Concentrating mechanism ; Corticomedullary gradients ; Urea ; Electrolytes ; Niere ; Konzentrierung ; Corticomedulläre Gradienten ; Harnstoff ; Elektrolyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An wachen, eiweißarm ernährten Wistar-Ratten wurde die Wirkung von Harnstoff auf die renale Wasserretention und Elektrolytkonzentrierung unter standardisierten Bedingungen (Trinkwasserentzug, mehrtägige kombinierte hypertone Harnstoff/NaCl-Infusion) untersucht. Die Ergebnisse lassen erkennen, daß Harnstoff aktiv aus den Sammelrohren resorbiert wird und daß Natrium bei Harnstoffzufuhr stärker im Nierenmarkgewebe angereichert wird als bei reiner Elektrolytinfusion. Die bei Harnstoffzufuhr erhöhten medullären Konzentrationen bewirken einen zunehmenden osmotischen Wasserentzug aus den Sammelrohren ins Interstitium. Die Harnvolumina nehmen bei Anstieg der Elektrolytkonzentrationen entsprechend ab. Es wird geschlossen, daß die wasserretinierende Wirkung des Harnstoffs am besten nachgewiesen werden kann, wenn — bei kalkulierter Wasser- und osmotischer Substanzzufuhr — die GFR konstant gehalten wird, weiterhin das Nephron hoch permeabel für Harnstoff ist, also bei maximalen medullären Natriumkonzentrationen und Harnstoff über längere Zeit bei gleichbleibender Konzentration infundiert wird.
    Notes: Summary Subject of the examinations was the special effect of urea to the renal water retention and electrolyte concentrating ability on protein lacking rats under standardized conditions (no drinking, long-term combined hypertonic urea/saline infusions). The results show, that urea is reabsorbed actively out of the collecting ducts and that sodium is better enriched in the renal medulla during simultaneous urea supply than with pure electrolyte infusion. These increased medullary concentrations cause an enlarged osmotic water removal out of the collecting ducts into the interstitium during urea supply so that the urine volumes decrease and the electrolytes are better concentrated in the urine. It is concluded, that the water retaining effect of urea could be proved best when the glomerular filtrates are kept unchanged, furthermore when the nephron is high permeable for urea, that is by maximal medullary sodium concentration, and when urea is infused by longterm supply in constant rations.
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  • 4
    ISSN: 1433-8580
    Keywords: Kidney ; Rat ; Ultrastructure ; Proximal tubule degeneration ; Heparinoid ; Niere ; Ratte ; Ultrastruktur ; Proximale Tubulusdegeneration ; Heparinoid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 24 Std nach i.v. Injektion von 100 mg/kg eines Pentosanschwefelsäureesters (SP 54) sind in der Nierenrinde von Ratten schwere degenerative Veränderungen der proximalen Tubuluszellen zu beobachten. Das Tubulusepithel ist flachkubisch umgewandelt, das Tubuluslumen ist angefüllt mit ausgestoßenen Mitochondrien und anderen Zelltrümmern. Am stärksten betroffen ist die Pars contorta des proximalen Tubulus. Weniger stark veränderte Tubuluszellen sind angefüllt mit Cytosomen, die eine spezifische Feinstruktur haben oder gehäuft gegenüber Kontrollen Cytoplasmaprotrusionen in das Tubuluslumen aufweisen. Die akute Tubulusdegeneration ist ein spezifischer Effekt von SP 54. Heparin bewirkt nur eine leichte Schwellung des Tubulusepithels, die häufiger auftritt als bei Kontrolltieren.
    Notes: Summary 24 hrs after the intravenous injection of 100 mg/kg of a Pentosansulfuricacidester (SP 54) severe degenerative alterations are observed in the proximal tubular cells in rat kidney cortex. The tubular epithelium has changed to a single layer of elongated cubic cells. The tubular lumen is filled with cellular debris and extruded mitochondria. The greatest change is seen in the pars contorta of the proximal tubule. Less degenerated tubular cells have a great number of cytosomes with a specific substructure or have cytoplasmatic protrusions into the tubular lumen. This acute tubular degeneration is a specific event after the administration of SP 54 and is not seen after an equimolar dosis of Heparin. Heparin induces only a slight swelling of the tubular epithelium, more frequent seen as in the control animals.
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  • 5
    ISSN: 1432-0568
    Keywords: X zone ; Electron microscopy ; Development ; Adrenal ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The postnatal development and involution of the X zone in the mouse adrenal cortex of both sexes were examined using the light and electron microscopes. At 0–5 days of age, no special cell group could be distinguished for the developing X zone in the inner cortex. The inner cortical cells contained spherical or ellipsoidal mitochondria with vesiculotubular cristae, vesiculotubular smooth endoplasmic reticulum (sER) and electron-lucent lipid droplets. The first sign of the developing X zone was the appearance of small groups of cells in juxtamedullary region differing from the cells in other part of inner cortex at 8 days. The electron microscopy showed that such cells contained nuclei of somewhat irregular outline and some parallel stacks of flattened sER. At 10–11 days, a thin layer of small eosinophilic cells were clearly identified as the developing X zone light microscopically in both sexes. Electron microscopically, the X zone cells showed a much dense cytoplas, which contained abundant sER, many mitochondria and numerous ribosomes. The typical X zone cells were characterized by the formation of peculiar mitochondrial complexes and whorled pattern of the sER. Mitoses were often found in the X zone, where mitotic cells even contained the whorled sER and bizarre mitochondria characteristic of the typical X zone cells. In the male the X zone rapidly involuted and might disappear by 30 days of age, whereas in the female X zone persisted as a thicker layer with the earlist sign of fatty degeneration. The origin of the X zone cell and the process of formation of its characteristic organelles are discussed.
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  • 6
    ISSN: 1432-0568
    Keywords: Colonic mucosa ; Mouse ; Vacuolated cells ; Electron microscopy ; Morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Swiss ICR adult male mice were used to analyse regional morphologic differences in the mucosa of the colon. The three cell types recently described in the descending colon of the mouse were also observed in the transverse and in the ascending colon. However the vacuolated cells of the crypts have presented different morphological characteristics depending on their localisation. In the ascending colon, they exhibited small supranuclear vesicles in contrast to the large vesicles observed in the descending colon. Several cell combining features of argentaffin-vacuolated, goblet-vacuolated and goblet-argentaffin cells have been observed. Furthermore a special type of granule referred to as a secondary lysosome was observed in the peripheral area of the typical goblet cells.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 144 (1974), S. 195-203 
    ISSN: 1432-0568
    Keywords: Development ; Adrenal glands ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Untersuchung der vorgeburtlichen Entwicklung der Nebennieren erfolgte an H.-E.-Schnitten und wurde ergänzt durch den Nachweis alkalischer Phosphatase. 1. Markzellen beginnen mit 11–12 Tagen in das Rindenblastem einzuwandern. Mit 14 Tagen a.p. ist die Einwanderung bereits abgeschlossen, d.h. viel früher als bei menschlichen Embryonen entsprechenden Alters. 2. Der Cortex beginnt sich am 11. Tag zu entwickeln, wie bei menschlichen Embryonen vergleichbaren Alters. Vor der Geburt kann bei der Maus nicht zwischen einem “fetalen” und “permanenten” Cortex unterschieden werden. 3. Eine frühzeitige Einwanderung von versprengten Geschlechtszellen kann in der Cortexanlage durch die Reaktion auf alkalische Phosphatase nachgewiesen werden. Später verschwinden sie wieder. Eine Infiltration von Leuko-und Lymphocyten besteht nicht. Beim Herannahen des Geburtszeitpunktes treten aber Blutbildungsherde auf.
    Notes: Summary A detailed reinvestigation of the prenatal development of the adrenal gland has been carried out, using H.-E. sections supplemented by investigation of alcaline phosphatase activity. 1. Medullary cells start to invade the cortex blastema at 11–12 days. Immigration is completed at 14 days a.p., i.e. much earlier than in human embryos of corresponding age. 2. Cortex development starts at 11 days, like in human embryos of corresponding age. Before birth, there is no distinction between “fetal” and “permanent” cortex in mice. 3. Early invasion of gonocytes into the cortex blastema can be demonstrated by alcaline phosphatase reaction. Later on they disappear. There is no infiltration of leuco-and lymphocytes. Near term foci of blood-forming cells are appearing.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 144 (1974), S. 205-214 
    ISSN: 1432-0568
    Keywords: Adrenal gland ; Juxtamedullary X-zone ; Mouse ; Development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die postnatale Entwicklung der Nebennieren wurde an hybriden Mäusen (Kreuzung der Inzuchtstämme C57BL/6 und CBA) und an nu/+ Mäusen (BALB/c) untersucht. Dabei standen uns von weiblichen und männlichen Tieren beider Stämme Schnittserien der folgenden Stadien zur Verfügung: 1, 7, 14, 21, 42, 63 und 84 Tage. Neben Zona glomerulosa und Zona fasciculata weist die Nebennierenrinde 2–3 Wochen alter Mäuse zwei innere Schichten auf. An die dem Mark anliegende, schon mehrfach beschriebene X-Zone schließt sich nach außen ein Gürtel kleiner Zellen an. Diese zwischen X-Zone und Fasciculata gelegene, bei Weibschen stärker ausgeprägte Rindenschicht bildet sich mit dem Verschwinden der X-Zone zurück. Wegen ihrer morphodynamischen und wahrscheinlich auch funktionellen Eigenständigkeit haben wir diese Schicht von der X-Zone abgetrennt und als kleinzellige Zone bezeichnet. Auf Grund unserer Beobachtungen neigen wir zur Ansicht, daß die definitive Zona reticularis aus der kleinzelligen Zone hervorgeht. Der Zeitpunkt beginnender Rückbildung der X-Zone zegt neben den bekannten geschlechtsabhängigen Unterschieden eine ganz erhebliche Variabilität (bis 10 Wochen) zwischen den verschiedenen Tierstämmen. Die X-Zone der Maus und die fetale Zone der menschlichen Nebenniere können—obwohl beides vorübergehende Strukturen—, wegen ihrer verschiedenartigen Entwicklung kaum als Analoga betrachtet werden.
    Notes: Summary The postnatal development of the adrenal glands was investigated in hybrid mice (from crossing the two inbred strains C57BL/6 and CBA) and in nu/+ mice (BALB/c). Serial sections of the following stages: day 1, 7, 14, 21, 42, 63, and 84 respectively from both strains and sexes were studied. The adrenal cortex of 2–3 week old mice is structurally differentiated into the zona glomerulosa, the zona fasciculata and two inner zones: 1: the well known x-zone surrounding the medulla; 2: a distinct zone (more pronounced in females, than in males) of small cells lying between the x-zone and the zona fasciculata. The latter disappears parallel to the removal of the x-zone. In view of the distinct morphological, developmental and probably even functional individuality of this zone, it was separated from the x-zone and given the name “zone of small cells”. It is assumed, that the definitive zona reticularis originates from the zone of small cells. The time at which the x-zone starts to degenerate depends on the sex, and varies considerably from one strain to another. The x-zone of the mouse and the fetal zone of the human adrenal gland—both transitory structures—differ too much in their development to be considered as analogous structures. New-born mice show a positive chromaffine reaction of the medullary cells. During the first 3 weeks the intensity of reaction increases considerably and then remains at the higher level for the time of further development.
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  • 9
    ISSN: 1432-0568
    Keywords: Development ; Genetics ; Mouse ; Vertebrae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The recessive mutation, rachiterata, reduces the number of cervical vertebrae to 6 by shifting the cervico-thoracic boundary in a cranial direction, and produces partial duplication of the neural arch of the axis. Rachiterata also produces malformations of thoraco-lumbar vertebrae, often associated with fusions of ribs. These malformations are caused by a disturbed arrangement of somites first detectable in 11-day embryos.
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  • 10
    ISSN: 1432-0568
    Keywords: Embryology ; Mouse ; Muscle differentiation ; Physiologic cell necroses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Mice embryos from day 9 to 15 p.c. have been studied by 1. Supravital staining of the whole embryo with nile blue sulfate. 2. Light and 3. Electron microscopic investigation of serial sections from the longitudinal axis of the back of the trunk. Nile blue sulfate staining revealed segmental necroses in the back of mice embryos centrally between the intersegmental arteries. Necroses appeared in the cranial myotomes and extended to the caudal ones during the days 9 to 13 p.c. By light microscopy the necroses extended in the centre of the myotome to the ventromedial margin. Electron microscopy revealed in this area myoblast-like cells rich in filaments, arranged in parallel without striation. A part of these myoblasts were electron-opaque and the nucleus was no longer evident. Forming vortices of filaments, these cells on the cranial and caudal end of the myotomes ceased fusion with the more centrally situated myoblasts. Vortices of filaments were also found in phagolysosomes of macrophages on day 12 p.c. On the same day of gestation we found an unsegmented myoblastema with irregular long myoblasts and striated polynuclear muscle fibres, arranged parallel to the neural tube. Between and parallel to the muscle fibres elongated individual cells could be seen, growing necrotic. Their nuclei were electron-dense with the chromatin clumping cap-like on the inner nuclear membrane. Fragments of myofibrils, corresponding approximately to sarcomeres, were dispersed irregularly as filament logs in the cytoplasm. Logs of filaments were bent at an obtuse angle, partly showing remnants of Z line material. In this stage of necrosis cells were phagocytized by macrophages. After disintegration of the segmental arrangement in scleroblastemata and myoblastemata a segmental rearrangement was not achieved by segmental shifting or by necrotic liquefaction zones. Whether the described cell necroses are due to differentiation, or even to phylogenetic causes is discussed.
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  • 11
    ISSN: 1432-0568
    Keywords: Dorsal lateral geniculate nucleus ; Morphology (ultrastructure) ; Mouse ; Synaptic vesicles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Neuronal perikarya, dendrites, extraglomerular neuropil, and synaptic glomeruli were examined by electron microscopy in the dorsal lateral geniculate nucleus (LGd) of the mouse. Particular attention was paid to boutons containing “flattened” synaptic vesicles. In line with recent studies of rat LGd (Lieberman and Webster, 1972; Lieberman, 1973), but in contrast to the findings of Rafols and Valverde (1973) on the mouse LGd, two distinct classes of ‘flat’-vesicle-containing boutons could be distinguished. P-boutons—were traced to and probably originate entirely from the presynaptic dendrites of the intrinsic neurons. They are concentrated within the glomeruli and are postsynaptic as well as presynaptic, being the intermediate elements in numerous intraglomerular serial synapses. F-boutons—are interpreted as axon terminals and are exclusively presynaptic. Some were traced from myelinated fibres. Synaptic vesicles are more concentrated in F-boutons than in P-boutons, appear flatter, and lie in a darker matrix. F-boutons synapse extensively in the extraglomerular neuropil, but are outnumbered by P-boutons in the glomeruli. The synaptic relationships established within the glomeruli are summarized.
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  • 12
    ISSN: 1432-0568
    Keywords: Leydig cells ; Differentiation ; Explants ; Ultrastructure ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Testes of newborn mice not older than one day were transplanted into the anterior chamber of one eye of an adult male white Holtzman rat. The events observed in the Leydig cells of the grafted testes can be divided into two periods. Period one is marked by differentiation; period two, by dedifferentiation. In period one, the lipid and glycogen inclusions disappear, possibly owing to the gonadotropins of the host. In period two, which starts after day 15 post-grafting, the lipids and glycogen reappear; the Leydig cells now contain residual bodies, whereas the S.E.R. disappears. Immunological mechanisms can be implicated; it is suggested that the Leydig cells dedifferentiate because the host's gonadotropins may be incapable of evoking and/or activating the genetic memory of the grafted Leydig cells.
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  • 13
    ISSN: 1432-0827
    Keywords: Serum ; Calcium ; Phosphate ; Alkaline phosphatase ; Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract In 30 patients with chronic renal insufficiency (16 non-dialysed and 14 on dialysis) serum calcium, phosphate and alkaline phosphatase were determined and, in a crest biopsy specimen, morphometric determinations of bone qualities were calculated. A positive correlation was established between serum alkaline phosphatase, the osteoblast surface and the active resorption surface in both dialysed and non-dialysed patients. A positive correlation was also established between the osteoblast surface and the active resorption. In the non-dialysed patients a negative correlation was established between serum calcium and the osteoid surface.
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  • 14
    ISSN: 1432-2013
    Keywords: Uric Acid Transport ; Hippurate Transport ; Organic Anions ; Kidney ; Liver
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experiments were designed to determine whether renal excretion of uric acid is achieved by the same mechanism as for renal tubular excretion of hippurates and related organic acids. Surviving slices of rabbit kidney cortex were unable to accumulate C14-urate by a concentrative mechanism. Further, entry of C14-urate into renal slices was unaffected by acetate, probenecid or anoxia in accord with earlier observations from this laboratory with non-radioactive urate. Experience with isolated perfused rat liver supports the use of this experimental method as a model of the hippurate transport system. Unlike hippurate and a large number of related organic anions, neither urate nor C14-activity derived from urate was concentrated in the bile from this preparation. Probenecid did not inhibit excretion of the small amounts of C14-activity which did appear in the bile. Urate did not compete with indigo carmine, a nonmetabolizable substrate of the hippurate transport system, for excretion into the bile. From these findings, it is concluded that urate and organic acids such as hippurate do not behave similarly in kidney or in liver. The possibility that urate might be excreted by an independent active transport mechanism is not excluded. The demonstration that renal tissues can synthesize urate from hypoxanthine raises the possibility that urate synthesis might also occur in the intact animal and might contribute to the renal clearance of uric acid.
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  • 15
    ISSN: 1432-2013
    Keywords: Kidney ; Tubular Reabsorption ; Tubular Maximum ; $$P_{CO_2 } $$ ; Plasma [HCO 3 − ]
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Renal reabsorption of bicarbonate was examined in Merino ewes. In all experiments the bicarbonate reabsorption was directly related to that of sodium. When the rate of bicarbonate reabsorption was expressed as the ratio of bicarbonate over sodium reabsorption, no tubular maximum for bicarbonate could be demonstrated. Arterial pH or $$P_{CO_2 } $$ did not affect the reabsorption of bicarbonate except through alterations in the plasma bicarbonate concentration. The ratio of bicarbonate over sodium reabsorption was directly proportional to the plasma concentration of bicarbonate over a wide range. This evidence suggests that the ionic reabsorption of bicarbonate constitutes a major part of total bicarbonate reabsorption. It does not, however, exclude a contribution from an active hydrogen ion secretory process, as the kinetic properteis of such a process are as yet undetermined.
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  • 16
    ISSN: 1432-2072
    Keywords: Locomotor Activity ; Mouse ; Morphine ; Narcotic Antagonists
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Morphine-induced locomotor activity in mice has been investigated but there appear to be only a small number of reports on the effects of narcotic antagonists on this increased activity. Also, it is well known that some narcotic antagonists can act as both morphine antagonists and analgesics in nociceptive assays, but there have been few demonstrations of this stimulant and antagonistic action with locomotor activity studies. In this study, six compounds (cyclazocine levallorphan, diprenorphine (M-5050), nalorphine, naloxone, and naltrexone) have been investigated in regard to their activity as antagonists of morphine-induced locomotor activity and in regard to their ability to stimulate locomotor activity themselves. All six compounds antagonized the effect of morphine, but only cyclazocine and levallorphan produced any significant stimulation of locomotor activity by themselves at the doses tested. This study indicates that changes in mouse locomotor activity can be used successfully to monitor the interaction between morphine and narcotic antagonists and that locomotor activity studies can also be used to study the stimulant (agonist) properties of narcotic antagonists.
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  • 17
    ISSN: 1432-2013
    Keywords: Kidney ; ATPase ; Transport ; Cortex ; Medulla ; Papilla
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The properties of microsomal ATPase were compared in the cortex, medulla and papilla of the rat kidney. 2. Activation of (Na+K)-dependent ATPase in the medulla was at lower potassium concentration than in the cortex or papilla. 3. (Na+K)-dependent ATPase in the papilla was more sensitive to ouabain than cortical or medullary ATPase. 4. (Na+K)-dependent ATPase in the kidney papilla was more sensitive to inhibition by calcium, cadmium andN-ethyl-maleimide than the enzyme from the kidney cortex or medulla. 5. Mg-ATPase in each region of the kidney was more resistant to inhibition by calcium, cadmium orN-ethyl-maleimide than the corresponding (Na+K)-dependent activity. 6. Mg-ATPase in the papilla was more resistant to inhibition by these inhibitors as well as by thiocyanate than the enzyme from cortex or medulla. 7. These data may suggest functional differences in the microsomal ATPase of various regions in the kidney.
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  • 18
    ISSN: 1432-2013
    Keywords: Kidney ; Renal Blood Flow ; Acute Renal Failure ; Renal Resistance ; Clearance Techniques ; Renal Venous Outflow ; Temporary Ischemia of the Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Total renal blood flow (RBF-dir) and total renal resistance were determined in acutely uninephrectomized rats by measuring the renal venous outflow after catheterizing the renal vein. Renal vein catheterization and the procedure involved caused an initial fall in C-IN and C-PAH followed by a steady level over an experimental period of 2–3 h. Absolute and fractional water excretion increased approx. 9-fold during that time. Mean RBF-dir was 14.2±0.67 (N=13) ml/min×kg BW×1 kidney. In another series of animals acute renal damage was induced by subjecting the kidneys to a 60 min period of temporary ischemia 3 days prior to use. RBF-dir decreased 10%, total renal resistance increased 11%, neither parameter being significantly different from controls. The clearance of inulin and PAH, the extraction ratio of PAH, and the urine flow rate were depressed to about 10% of control (P〈0.001). A considerable discrepancy was found between data obtained by clearance methods and RBF-dir after ischemia: The ratio RPF-PAH/RPF-dir was 1.05 under control conditions and was significantly depressed to 0.47 (P〈0.005) after ischemia.—These results indicate that a general increase in resistance of the vasa afferentia alone cannot be responsible for the oliguric phase. At least two important factors are involved in the cause of oliguria 3 days after temporary ischemia: Backdiffusion of tubular fluid through the damaged tubular epithelium and a decrease in GFR.—Clearance methods are not considered to be reliable determinants of GFR and RPF in renal failure after temporary ischemia.
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  • 19
    ISSN: 1432-2013
    Keywords: Paracellular Shunt Pathway ; Transtubular Permeability ; Perfused Toad Kidney ; Transtubular Osmotic Gradient ; Kidney ; Epithelia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Trace amounts of either labelled mannitol, sucrose, raffinose or inulin were added to the portal circulation in the doubly perfused toad kidney and their-urine-to-portal fluid, labelled molecules-to-chemical inulin ratio (denoted here asR) was evaluated. Under control isosmotic conditionsR was found to be inversely related to the probing molecule radius.R for inulin was practically zero.R for all probing molecules rose reversibly when the luminal fluid was rendered hyperosmotic by addition of 50 mmole mannitol to the aortic circulation, and even more so when 50 mmole urea was added per liter of aortic fluid. ThusR for raffinose rose from 0.0025±0.0002 (control) to 0.0126±0.0012 (+50 mM mannitol) and to 0.0967±0.0112 (+50 mM urea). This increase inR must be due to widening of the paracellular shunt pathway since the contribution of portal circulation to the glomerular filtrate was negligible and these molecules are known to stay extracellular. The present experiments suggest that transtubular urea (and osmotic) gradients may play a role in the regulation of the size of the paracellular shunt pathway.
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  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Pediatric radiology 2 (1974), S. 39-41 
    ISSN: 1432-1998
    Keywords: Kidney ; blood flow ; circulation time ; reflux ; pyelonephritis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The intrarenal circulation time in rabbits was found to decrease when the intrapelvic pressure was elevated acutely. A possible explanation is a redistribution of the blood flow with part of the blood effectively by-passing some renal parenchyma and thereby hypothetically resulting in local ischaemia. At vesico-ureteral reflux the same mechanism may cause repeated episodes of ischaemia. This may well happen particularly in areas drained by a damaged papilla, where rises in the intra-pelvic pressure may be conducted directly into tubuli and peritubular capillaries and veins.
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  • 21
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 351 (1974), S. 323-330 
    ISSN: 1432-2013
    Keywords: Uricase ; Urate ; Allantoin ; Liver ; Kidney ; Microperfusion ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. In vivo uricase activity was tested in rats by injection of 2-C14 urate and measurement of the total C14 activity and the fractional activities of allantoin, allantoic acid and urea in samples of blood and urine. In control animals, 5 min after the injection, 70% of the plasma tracer was already present in the form of allantoin. No allantoic acid and urea were produced. Intestinectomy had no measurable influence on uricase activity. On the other hand, hepatectomy or ligation of the hepatic artery combined with subtotal viscerectomy did abolish uricase activity almost completely. 2. Following microinjections into proximal tubules of Ringer solution containing 2-C14 urate, urine samples during early recovery mainly contained labelled urate, whereas in later samples the fraction of labelled allantoin increased. About 12 min after the microinjection the urine of both kidneys contained equal amounts of tracer mainly in the form of allantoin. 3. When segments of proximal tubules were perfused with an equilibrium solution containing tracer amounts of C 14 urate, no urate was metabolized during its passage through the proximal tubule. 4. C 14 urate was offered from the peritubular capillaries and samples of tubular fluid were analyzed, Again, all the tracer in the tubular fluid was in the form of urate, indicating that urate is not oxidized when it is transported across the tubular cell. It is concluded from these results that: 1. The rat kidney has no significant uricase activity. 2. Urate transport in the kidney is not influenced by this enzyme. 3. The degradation of urate to allantoin takes place at extrarenal sites, mainly in the liver.
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  • 22
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 148 (1974), S. 381-396 
    ISSN: 1432-0878
    Keywords: Placenta ; Mouse ; Syncytium ; Morphogenesis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'origine embryologique des constituants cytologiques de la barrière placentaire chez la Souris a été mise en évidence du 8ème au 11éme jour de la gestation et la séquence des phénomènes favorisant la formation d'un syncytium trophoblastique, précisée. La barrière placentaire trilaminaire a une double origine: la couche interne provient du trophoblaste chorionique, la couche médiane syncytiale comme la couche externe dérivent du trophoblaste ectoplacentaire. Le stimulus initial de la différenciation semble résulter au 9ème jour du contact entre le trophoblaste chorionique et le mésoderme allantoïdien. Quelques heures après, on observe la réaction des cellules chorioniques, caractérisée par une augmentation importante des nucléoprotéines cytoplasmiques, puis l'apparition de globules lipidiques et enfin des propriétés de motilité. Ces cellules établissent des jonctions complexes avec le trophoblaste ectoplacentaire indifférencié qu'elles côtoient. En même temps, le métabolisme nucléaire de ces cellules ectoplacentaires semble modifié. Ultérieurement, au 10éme jour de la gestation, la disparition des membranes plasmiques latérales de ces cellules, conduit à la formation d'un syncytium par fusion de cellules au même stade d'évolution.
    Notes: Summary The morphogenesis of the different layers forming the mouse placental barrier is described during the 8th to 11th day of gestation. The timing and events leading to the formation of the syncytiotrophoblast are analyzed. Two different processes lead to the formation of the hemotrichorial placental membrane: the internal layer is formed by the chorionic trophoblast, both the intermediate syncytial layer and the external cytotrophoblast layer are derived from the ectoplacental trophoblast. The differentiation of the placental barrier begins on the 9th day of gestation by the establishment of contact between the chorionic trophoblast and the allantoic mesoderm. A few hours later, the chorionic cells show a considerable increase in cytoplasmic nucleoproteins and lipids and become ameboid. Complex cell-junctions differentiate between these chorionic cells and the adjacent ectoplacental trophoblast. On the 10th day of gestation the lateral cytoplasmic membranes disappear leading to the formation of a syncytium.
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  • 23
    ISSN: 1432-0878
    Keywords: Kidney ; Sexual segment ; Natrix natrix ; Histochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The sexual segment of the kidney of Natrix natrix has been investigated cytochemically, light microscopically and ultrastructurally. The sexual segment, which seems to be an important accessory sexual organ, has a single layer of a columnar epithelium. The epithelial cells are filled with large secretion granules of a wide range of electron densities. Cytochemical reactions for neutral and acid mucosubstances are negative, but the cells show a strong positive staining for phospholipids. Within the cells of the sexual segment we have localised by histochemical means several hydrolases and oxydoreductases, which reflect enzyme activities of the glycolytic pathway, the citrate cycle, and related metabolic pathways. The activities of the hydrolytic enzymes acid phosphatase, acetylcholinesterase and indoxylacetate esterase are remarkably high within the epithelial cells. Furthermore it was found that the sexual segment tubules possess contractile elements which extends over the basal surface of the epithelial cells. These contractile cells exhibit a very high activity of alkaline phosphatase. Single unmyelinated axons are located between the contractile elements and the basal lamina of the sexual segment cells. The functional significance of the sexual segment structures is briefly discussed.
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  • 24
    ISSN: 1432-0878
    Keywords: Neural lobe ; Mouse ; Growth and development ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Nerve fibres of the neurosecretory hypothalamo-hypophyseal tract were studied in embryonic C3H mouse neural lobes; at least four glands at each gestational day 15–19 were examined. Single axons and small bundles of fibres are visible at gestational days 15 and 16. By day 17 large fibre bundles penetrate between glial cells. They increase in number during the next two days. Electron-lucent and electron-dense vesicles are seen in the fibres of the 15th and 16th gestational days. In the 17–19 day-old embryos development is characterized by a successive rise in the number of the two types of vesicles. The mean diameter of the electron-lucent vesicles is approximately unchanged in all the stages examined (50 nm). The electron-dense vesicles increase in size from approximately 80–90 nm at days 15–16 to 140 nm at the 19th gestational day. By day 19 contacts between neurosecretory fibre terminals and the outer basement membrane of internal and peripheral capillaries are occasionally observed. The possibly adrenergic nature of a few terminals contacting peripheral vascular structures in 17 and 18 day-old embryos is suggested.
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  • 25
    ISSN: 1432-0878
    Keywords: Pituitary ; Mouse ; Pars intermedia ; Adrenoglomerulotropin ; Morphometric cytology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural changes in the pars intermedia of the mouse pituitary caused by dietary sodium deprivation were investigated quantitatively. Of the six classes of organelles and inclusions selected for analysis in the pars intermedia cells, only the mitochondria showed no significant changes, while all of the remaining classes showed statistically significant changes. The most conspicuous changes were an abrupt decrease in the number of secretory granules and the appearance of parallel arrays of rough endoplasmic reticulum. The Golgi apparatus also showed hypertrophy accompanied by newly formed granules. The number of vesicles increased temporarily and then decreased. These findings indicate that dietary sodium depletion, a stimulus to greater aldosterone secretion, causes significant changes in the pars intermedia cells within 3 days, and these signs of hyperfunction last up to 5 days. The present study suggests a possible new role of the pars intermedia in the regulation of aldosterone secretion in response to dietary sodium deprivation in the mouse.
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  • 26
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 147 (1974), S. 183-190 
    ISSN: 1432-0878
    Keywords: Kidney ; Rat ; Bowman's capsule ; Experimental hypertension
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The parietal layer of Bowman's capsule was examined in the rat in control animals and in animals made hypertensive by treatment with desoxycorticosterone acetatesaline and by clipping of the renal artery. At an early stage of elevation of blood pressure and, occasionally, prior to elevation of blood pressure, the epithelial cells of this layer showed basal cytoplasmic protrusion and reduplication accompanied by an increase in the thickness of the basement membrane. These changes preceded evidence of glomerular or renal arteriolar pathology. They presumably reflect either a response of this layer to increased blood pressure and modified glomerular function, or a direct effect of the factors that also induces blood pressure elevation. In either case, they imply a greater functional significance for the parietal layer than has usually been attributed to it.
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  • 27
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 150 (1974), S. 323-329 
    ISSN: 1432-0878
    Keywords: Spermiogenesis ; Mouse ; Multinucleate spermatids ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscope studies of the testes of five inbred and three outbred mouse strains show that the usual frequency of multinucleate spermatids is between one and two percent. In C57 BL/6J and A/Gr however it is higher (4–5%). The frequency of the shared acrosome condition, which would lead to the formation of an abnormal sperm, is 1.3 per thousand.
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  • 28
    ISSN: 1432-1912
    Keywords: 5-HT Synthesis Rate ; MAO Inhibitors ; Probenecid ; Ro4-4602 ; Tryptophan ; Brain ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Non-isotopic and isotopic methods were used to estimate the rate of 5-HT synthesis in the mouse brain. 5-HT and 5_HIAA levels were measured in tissues up to 10 min after the i. p. injection of pargyline (75 or 150 mg/kg) or pheniprazine (5 or 10 mg/kg) (5-HT and 5-HIAA, MAO-inhibitor methods). 5-HIAA levels were also estimated at various times after probenecid administration (200 or 400 mg/kg i. p.) (5-HIAA-probenecid method). 5-HTP levels were estimated at various times after the blockade of 5-HTP decarboxylase by Ro4-4602. (800, 1000 or 1200 mg/kg i. p.) (5-HTP method). Finally the rate of conversion of tryptophan into 5-HT has been estimated by measuring the initial accumulation of 3H-5-HT and 3H-5-HIAA in tissues following the intravenous injection of 3H-tryptophan (isotopic method). Rates of 5-HT synthesis obtained with the two MAO inhibitor methods were much higher (about 3 to 4 times) than those calculated with the 5-HTP and 5-HIAA-probenecid methods. An intermediate rate of 5-HT synthesis was found with the isotopic technique. The high rate of 5-HT synthesis observed with the 5-HT, MAO inhibitor method (about 8 nmoles/g/h) was not related to a stimulation of 5-HT synthesis. Differences seen with all methods are discussed with respect to results obtained by various groups of workers.
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  • 29
    ISSN: 1432-1912
    Keywords: Kidney ; Adrenaline ; Catechol-O-methyltransferase (COMT) ; Inhibition ; H22/54 [(±)-α-Dihydroxyphenyl]-n-valeramid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In the dog kidney catecholamines are O-methylated before being secreted by the tubule (Hempel et al., 1973). Adrenaline was used in an investigation to determine whether or not O-methylation is a prerequisite for the tubular secretion of a catecholamine in the dog. In dogs (n=3) treated with the COMT inhibitor H22/54 [(±)-α-(3,4-dihydroxyphenyl)-n-valeramid] the excretion of 14C-(±)-adrenaline and the pattern 14C-adrenaline metabolites in urine were measured. 14C-adrenaline (9.2 μg per injection) was injected simultaneously with 3H-inulin into both renal arteries. Eigth injections of radioactive material were given to each animal. COMT was inhibited before the second 14C-adrenaline injection by infusion of H22/54 into the left renal artery in doses of 0.16, 0.72 and 3.2 mg/kg b.w., respectively. Without H22/54 the injected dose of 14C-adrenaline was excreted by the kidney within 12 min as followed: 22.2 ± 6.0% (n=6) as 14C-adrenaline, 21.8 ± 7.0% (n=7) as 14C-metanephrine, and 9.3 ± 2.2% (n=7) as deaminated or conjugated 14C-adrenaline metabolites. H22/54 reduced the excretion of 14C-metanephrine to 9–28.2% of the control value, whereas the 14C-adrenaline excretion was considerably increased, up to 200% of the control. It is concluded that the additional 14C-adrenaline observed in urine after COMT inhibition was secreted by the tubule. Thus, O-methylation seems not to be a prerequisite for tubular secretion of adrenaline in the dog.
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  • 30
    ISSN: 1432-1912
    Keywords: 5,7-Dihydroxytryptamine ; Chemodegeneration ; Adrenergic Nerves ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Injections of 5,7-dihydroxytryptamine (60 mg/kg, i.p.) caused a significant reduction in the noradrenaline content of the mouse heart, large intestine and seminal vesicle, 2 and 6 days after drug application. The long-lasting depletion of noradrenaline was found to be due to a degeneration of adrenergic nerve terminals as verified by fluorescence and electron microscopical observations. The results show that 5,7-dihydroxytryptamine is either as potent as (e.g. in the heart) or less potent than 6-hydroxydopamine (e.g. in the vas deferens) in depleting noradrenaline. The pronounced effects of 5,7-dihydroxytryptamine on the adrenergic nerves of the seminal vesicle (supplied by the same short adrenergic neurones as the vas deferens) suggest that 5,7-dihydroxytryptamine may be used as a tool for the induction of a chemical sympathectomy in certain peripheral organs of laboratory animals, supplementary to 6-hydroxydopamine.
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  • 31
    ISSN: 1435-2451
    Keywords: Kidney ; Organ Preservation ; Transplantation ; Niere ; Organkonservierung ; Transplantation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Nierentransplantation ist eine wesentliche Ergänzung der Dauerdialysebehandlung geworden. In der Bundesrepublik Deutschland ist die Transplantationsfrequenz jedoch sehr niedrig. Dies ist enter anderem auf den Mangel an Spenderorganen zurückzuführen. Die Ausstellung hatte zum Ziel, die Methodik der Organentnahme und der Organkonservierung Bowie die notwendigen organisatorischen Maßnahmen aufzuzeigen. Die in der BRD aktiven Transplantationszentren wurden aufgeführt, um die Beteiligung anderer Kliniken an der Transplantationschirurgie anzuregen.
    Notes: Summary Kidney transplantation is an essential complement to chronic dialysis, but the frequency of transplantation is very low in the Federal Republic of Germany. One reason is the shortage of donor organs. The exhibition demonstrates the method of organ exstirpation and preservation of the organs as well as describing the necessary administrative measures: A list of the transplantation centres in the Federal Republic of Germany is given to encourage other clinics to become involved in kidney transplant operations.
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  • 32
    ISSN: 1433-8580
    Keywords: Amiloride ; Autoradiography ; Kidney ; Potassium-saving Diuretics ; Amilorid ; Autoradiographie ; Niere ; Kaliumsparende Diuretica
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Nierenaufnahme und intrarenale Verteilung von14C-Amilorid wurde nach intramuskulärer Injektion an Mäusen untersucht. 30 min nach der Injektion von 0,5–5 mg Amilorid/kg wurden Aktivitäten gemessen, die einer renalen Konzentration von 30–650 ng Amilorid/g Niere entsprechen. Der Quotient Nierenaktivität/Plasmaaktivität lag dabei zwischen 13:1 und 20:1. Anzeichen für eine Sättigung der renalen Amiloridanreicherung waren bis zu einer Dosis von 5 mg Amilorid/kg nicht zu beobachten. Mit Hilfe der Gefrierschnittautoradiographie wurde festgestellt, daß14C-Amilorid sich nach intramuskulärer Injektion vor allem im terminalen Hauptstück des Außenstreifens und im Sammelrohrlumen anreichert. Da die gleiche intrarenale Verteilung nicht nur bei anderen, im proximalen Tubulus sezernierten organischen Basen wie z. B. Histamin, sondern auch bei den sezernierten organischen Säuren wie PAH, Phenolrot, Diodrast und Furosemid vorkommt, wird für solche Bilder die Bezeichnung „proximal-sekretorisches Verteilungsmuster“ vorgeschlagen. An Hand seiner intrarenalen Verteilung werden mögliche Zusammenhänge zwischen dem Wirkungsort, dem vermuteten Wirkungsmechanismus und der Konzentration von Amilorid entlang des Nephrons diskutiert.
    Notes: Summary The renal uptake and intrarenal distribution of14C-Amiloride was studied after intramuscular injection in mice. 30 min after injection of 0.5–5.0 mg Amiloride/kg body weight, renal activities were found corresponding to 30–650 ng Amiloride/g kidney. The ratio of renal/plasma activity ranged between 13:1 and 20:1. Neither renal concentration nor this ratio reached saturation levels with doses up to 5.0 mg Amiloride/kg body weight. Cryostat section autoradiography showed high14C-Amiloride-concentrations mainly in the terminal portion of the proximal tubule (in the outer stripe of the outer medulla) and in the lumen of the collecting ducts. As identical distribution patterns have been found for other organic bases secreted in the proximal tubule (e.g. histamine) and organic acids (e.g. PAH, phenol red, Diodrast and Furosemide) the term “proximal secretory distribution pattern” for this type of radiographic image is proposed. Correlations between the mechanism and locus of action and the concentration of Amiloride in the divers segments of the nephron are discussed on the basis of the intrarenal distribution pattern.
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  • 33
    ISSN: 1433-8580
    Keywords: Mineralisation ; 85Sr ; Graft ; Bone ; Mouse ; Mineralisation ; 85Sr ; Transplantat ; Knochen ; Maus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Durch wiederholte Messung der 48 Std-Retention von85Sr zu verschiedenen Zeiten nach der Transplantation wurde die Kapazität zur Aufnahme von Erdalkali bei Tibiatransplantaten junger Mäuse unter verschiedenen immunologischen Bedingungen über einen Zeitraum von 36 Tagen nach der Transplantation verfolgt. Bei syngenen Transplantaten war die85Sr-Aufnahme bis zum 10. Tag nach der Transplantation gleich derjenigen der allogenen Transplantate. Danach stieg sie steil an bis zum 17. Tag und blieb bis zum Ende des Versuchs (36 Tage nach Transplantation) auf dem Niveau der Empfängertibia. Sowohl syngen als auch allogen transplantierte Tibiae zeigten nach der Transplantation eine etwa gleichstarke Zunahme der Aschegewichte.
    Notes: Summary In growing tibia transplants of the mouse the 48-hour uptake of85Sr was determined. With allogeneic grafts the uptake was continuously low during 32 days after transplantation. With syngeneic grafts uptake was low up to the 10th day after grafting. After 17 days, however,85Sr uptake was higher than that of allogeneic ones. Ashweights of both groups of transplants were higher at the end of the experiment than at the time of grafting.
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  • 34
    ISSN: 1432-0568
    Keywords: Cleavage stages ; Egg-cylinder ; Mouse ; Rat ; Hydrolytic enzymes distribution ; Differentiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The time of appearance and the distribution of alkaline and acid phosphatase and nonspecific esterase was investigated in cleavage and early postimplantation stages of mouse and rat embryos. Alkaline and acid phosphatase appeared for the first time in 8-cell embryos. Activity of both enzymes grew progressively stronger to blastocyst stage. Acid phosphatase activity was revealed in the form of fine and coarse granules distributed evenly in the cytoplasm. Alkaline phosphatase was predominantly localized in plasma membranes. There was no difference in intensity of reaction between trophoblastic cells and the inner cell mass. After implantation acid phosphatase was localized in coarse granules in the apical portion of entodermal cells. With the appearance of mesoderm, the cells of embryonal entoderm became flattened and devoid of acid phosphatase activity which was restricted to cells of extraembryonic entoderm. The activity of nonspecific esterase was not detected in preimplantation stages. In postimplantation embryos it roughly corresponded to the activity of acid phosphatase. Alkaline phosphatase was localized in cell membranes of ectodermal cells. The mesodermal cells of mouse embryo displayed a somewhat weaker activity than ectodermal cells, while in the rat embryo the same layer remained completely nonreactive. Our findings on the distribution of the enzymes mentioned did not reveal any kind of polarity or bilateral symmetry in preimplantation stages. In postimplantation stages acid phosphatase and nonspecific esterase are probably bound to lysosomes and play an important role in embryonic nutrition. The absence of alkaline phosphatase from entodermal cells is somewhat puzzling and suggests that the process of molecular transport in those cells is most probably restricted to endocytosis. Our results suggest that all blastomeres are identical with respect to enzyme distribution and that the first signs of differentiation of enzyme content appear with the formation of germ layers.
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  • 35
    ISSN: 1432-0568
    Keywords: Lymphocytes ; Thymus ; Karyometry ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Karyometric studies were made of lymphocytes for the cortex and medulla of the thymus of mice at various ages from birth to adulthood. From the results obtained it was evident that in early neonate mice, medullary small lymphocytes were characterized by having larger nuclei than cortical small lymphocytes. On the basis of cytological features, such medullary lymphocytes could reasonably be classified as small lymphocytes rather than medium lymphocytes, although they had larger nuclei than typical small lymphocytes. Such peculiar small lymphocytes with larger nuclei were preponderant in the medulla during early neonatal life, but they rapidly decreased in number with advancing age, although they were present in a small proportion even in adults. The findings on the occurrence of such peculiar small lymphocytes in the medulla were discussed in relation to the maturation pathway of lymphocytes in the thymus.
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  • 36
    ISSN: 1432-0568
    Keywords: Peroxisomes ; Microbodies ; Catalase ; Ciliated cells ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Flimmerepithel aus Respirationstrakt (Nasenseptum, Trachea) und Tube der Maus wurde untersucht. Nach Fixierung in 5% nicht destilliertem Glutaraldehyd wurde das Gewebe zur Darstellung der peroxydatischen Aktivität von Katalase in einem alkalischen Medium (pH 8,0 und 9,5) von 0,2% DAB und 0,02% H2O2 inkubiert. In den Flimmerzellen wird durch die histochemische Reaktion die granuläre Matrix kleiner Zellorganellen elektronendicht dargestellt. Diese Organellen sind im Schnitt rund, oval oder tubulär; Sie werden von einer Einheitsmembran begrenzt. Die Größe ihrer kurzen Durchmesser schwankt zwischen 0,1 und 0,2 μm. Schlauchförmige Partikel sind bis 1 μm lang. Die histochemische Reaktion wird durch 2×10−2 M 3-Amino-1,2,4-Triazol im Inkubationsmedium gehemmt und fehlt, wenn ohne H2O2 im Medium inkubiert wird. Die Interpretation dieser Organellen als echte Peroxysomen einzig auf Grund ihres Katalasegehalts wird diskutiert. Um den Forderungen des von de Duve entwickelten Peroxysomenkonzepts zu genügen, wäre der Nachweis von H2O2 erzeugenden Oxydasen Voraussetzung. Bis dahin muß der Terminus Peroxysom für Partikel, in denen nur Katalase nachgewiesen ist, als Arbeitshypothese aufgefaßt werden.
    Notes: Summary Ciliated cells in the epithelium of the respiratory tract (septum nasi, trachea) and oviduct of mice were investigated. The tissue was fixed in 5% undistilled glutaraldehyde and incubated in an alkaline (pH 8.0 and pH 9.5) medium containing 0.2% DAB and 0.02% H2O2, to demonstrate the peroxidatic activity of catalase. In ciliated cells the granular matrix of small cell organelles is intensely stained by the histochemical method used. These particles are round, oval or tubular in shape, they are limited by an unit membrane. Their short axes measure from 0.1 to 0.2 μm. Tubular shaped particles are up to 1 μm long. The histochemical staining reaction is abolished by the addition of 2×10−2 M 3-amino 1,2,4-triazole to the incubation medium or if H2O2 is omitted from the medium. The interpretation of these particles as true peroxisomes on account of their catalase content only is discussed. It is concluded that the demonstration of peroxide producing oxidases would be necessary to satisfy the conditions of the peroxisome concept, which was proposed by de Duve. So far, the term peroxisome for particles which are only demonstrated to contain catalase, must remain a working hypothesis.
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  • 37
    ISSN: 1432-0568
    Keywords: Retina ; Mouse ; Photoreceptors ; Differentiation ; rd Mutant
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Mice, homozygous for the mutant gene rd show selective degeneration of the photoreceptor cells after their initial differentiation. Phenotypic expression in the mutant and in normal mice was studied by light and electron microscopy. The sequential emergence of developmental deviations in the mutant retina falls into three categories. First, predegenerative differences are manifest within the photoreceptor cells during 4–8 days after birth in retarded growth of the inner segments, reduced outer segment production, delayed development of the outer plexiform layer and slower segregation of the perikarya. Next, degenerative changes are recognized from 6 day onwards with swelling and vacuolization of the Golgi cisternae in the inner segments followed by cytolytic alterations affecting the ultrastructure of the entire cell. Lastly, with increasing loss of photoreceptor cells post-degenerative effects are seen in deepening of the basal infoldings and microvilli of the pigment epithelium and increase of Müller's fibres. The progress of degeneration in the mutant retina corresponds to the phase of rapid growth of the Golgi apparatus and rod outer segments in the normal retina. The role of the Golgi apparatus in the differentiation of the photoreceptor cells and its relation to the expression of the rd gene are discussed.
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  • 38
    ISSN: 1432-0827
    Keywords: Osteopetrosis ; Diphosphonates ; Bone Resorption ; Mouse ; Calcium ; Tooth ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'effet de doses quotidiennes, administrées depuis la naissance, de deux types de diphosphonates, à savoir l'éthane-1-hydroxyle-1,1-diphosphonate (EHDP) et le dichlorométhylène diphosphonate (Cl2MDP), sur la croissance et le squelette de souris a été étudié. Les diphosphonates freinent la croissance: les incisives ne font pas leur éruption ou elle est plus tardive. La calcémie est normale. L'administration de Cl2MDP à une dose quotidienne de 10 mg P/kg/jour provoque des modifications squelettiques identiques à celles des souris grises létales atteintes d'ostéopétrose et les animaux meurent après quatre semaines de traitement. Par rapport aux témoins, les souris traitées présentent des os plus étroits, plus denses et plus déformés: les cavités médullaires sont comblées avec de l'os calcifié et du cartilage. La quantité totale de calcium d'un animal n'est pas augmentée par traitement au diphosphonate, par rapport à un témoin de même âge. Chez les souris grises létales et celles traitées aux diphosphonates, la plupart des anomalies est secondaire à une résorption osseuse diminuée. Ces résultats sont commentés en fonction de l'emploi des diphosphonates au cours de remaniements osseux pathologiques augmentés et en fonction du rôle de la résorption osseuse dans le maintien de la calcémie.
    Abstract: Zusammenfassung Mäuse erhielten von der Geburt an tägliche Dosen folgender zwei Diphosphonate: entweder Äthan-1-Hydroxy-1,1-Diphosphonat (EHDP) oder Dichloromethylen-Diphosphonat (Cl2MDP). Es wurde deren Wirkung auf das Wachstum und das Skelet untersucht. Die Diphosphonate verlangsamten das Wachstum, die Schneidezähne brachen nicht oder erst später durch, aber die Höhe des Plasmacalciums blieb normal. Die Verabreichung von Cl2MDP in Dosen von 10 mg P/kg/Tag führt zu Skeletveränderungen, welche denjenigen der „grey-lethal” osteopetrotischen Mäuse gleichen. Die Tiere sterben nach einer Behandlungsdauer von etwa 4 Wochen. Verglichen mit normalen Mäusen von ungefähr gleichem Alter hatten die behandelten Mäuse kleinere, dichtere und mehr keulenförmige Knochen, und die Markhöhlen waren gefüllt mit verkalktem Knochen oder Knorpel. Die Gesamtcalciummenge im Skelet wurde durch die Diphosphonatbehandlung nicht erhöht; dies ergab sich aus einem Vergleich mit der bei normalen Mäusen desselben Alters gefundenen Menge. Es wird vorgeschlagen, daß bei den „grey-lethal” und bei den Diphosphonat-behandelten Mäusen viele der Abnormalitäten als Folge der herabgesetzten Knochenresorption angesehen werden müssen. Die Ergebnisse werden einerseits im Hinblick auf den Gebrauch der Diphosphonate bei pathologischen Bedingungen eines erhöhten Knochenumbaus diskutiert; andererseits werden sie im Zusammenhang mit der Rolle der Knochenresorption bei der Erhaltung des Plasmacalcium-Spiegels besprochen.
    Notes: Abstract The effect of daily doses from birth of two diphosphonates, namely either ethane-1-hydroxy-1,1-diphosphonate (EHDP) or dichloromethylene diphosphonate (Cl2MDP), on the growth and the skeleton of mice has been studied. Diphosphonates slowed growth, the incisors did not erupt or erupted later, but the level of plasma calcium remained normal. The administration of Cl2MDP at a dose rate of 10 mg P/kg/day leads to skeletal changes that are similar to those observed in grey-lethal osteopetrotic mice, and the animals die after about four weeks of treatment. As compared with normal mice of similar age, treated mice had bones that were smaller, denser and more clubshaped, and the marrow cavities were filled with calcified bone or cartilage. The total amount of calcium in the carcass was not increased by diphosphonate treatment, as compared with the amount in normal mice of the same age. It is suggested that both in the grey-lethal and diphosphonate-treated mice many of the abnormalities are secondary to decreased bone resorption. The results are discussed with respect to the use of diphosphonates in pathological conditions of increased bone turnover and with respect to the role of bone resorption in the maintenance of plasma calcium levels.
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  • 39
    ISSN: 1433-8580
    Keywords: Organ preservation ; Kidney ; Organ damage ; Hypothermia ; Perfusion ; Nuclear medicine ; Organkonservierung ; Niere ; Organschädigung ; Hypothermie ; Perfusion ; Nuclearmedizin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Funktionstüchtige und experimentell geschädigte Hundenieren wurden zur Konservierung im Belzer-Gerät hypotherm perfundiert. Die Beurteilung des Organzustandes erfolgte mit herkömmlichen Methoden (Druck/Flow-Relation, Organgewicht, Replantationsergebnis). Gleichzeitig wurden nuclearmedizinische Verfahren erprobt, mit dem Ziel, zu jeder Zeit der Konservierungsphase definitiven Aufschluß über die nach Replantation zu erwartende Funktionstüchtigkeit des Organs zu erhalten. Mit Hilfe von J131-o-Hippursäure konnte gezeigt werden, daß die Tubulusfunktion bei 5°C ruht und unter Hypothermiebedingungen nicht als Gradmesser für den Organzustand in Betracht kommt. Demgegenüber erwies sich ein sequenzszintigraphisches Verfahren als brauchbar, bei dem der In113m-EDTA-Durchsatz durch die Niere mit Hilfe eines Szintillationskamera-Computersystems bestimmt wurde. Aus Zeit-Aktivitäts-Verläufen ermittelte Parameter gaben im gesamten Konservierungsverlauf zuverlässig Aufschluß darüber, ob ein Organ intakt bzw. mehr oder weniger geschädigt war.
    Notes: Summary Uninjured as well as experimentally damaged kidneys of dogs were preserved by hypothermic perfusion according to the method of Belzer. The functional conditions of the organs were estimated by conventional methods. At the same time nuclear medical procedures have been tried in order to get more reliable information about the probable degree of organ damage at any time of the preservation phase. By means of J131-Hippurate it could be established that renal tubuli are not working at a temperature of 5°C. Therefore, Hippurate clearance can not be used as a criterion of the functional state under hypothermic conditions. Contrary to this finding the manner of transit of In113m-EDTA through the kidney yielded useful parameters for valuation of the organ. For the present investigations a Scintillation Camera-Computer System has been used which can, for routine purposes, be substituted by a simple scintillometer-recorder system.
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  • 40
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 12 (1973), S. 117-124 
    ISSN: 1432-0827
    Keywords: Mouse ; Calcification ; Metals ; Mast Cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des souris, ayant reçu par voie intra-veineuse une solution d'acétate de plomb, sont injectés par voie sous-cutanée avec du sulfate de polymixine B. Au niveau de ce dernier point d'injection, on observe des calcifications. L'examen histologique montre une dégranulation des mastocytes, une vaso-dilatation locale ainsi qu'une diffusion d'ions à partir des vaisseaux. Après 24 heures, des ions calcium et phosphate sont présents. En outre. des groupes de souris, pré-injectées par voie intraveineuse avec de l'acétate de plomb, reçoivent des extraits de granules de mastocytes, comportant du phosphate d'histamine, du sulfate de créatinine sérotonine, de l'héparine, du sulfate de chondroitine ou de l'acide hyaluronique. Seules les injections de sérotonine et d'histamine, connues comme vaso-dilatateurs et augmentant probablement la perméabilité capillaire, provoquent des calcifications. Il semble que le rôle des mastocytes dans la calcification soit lié principalement à la production d'une vasodilatation locale, avec perméabilité capillaire augmentée, plutot qu'à une action de liaison initiale des ions métalliques.
    Abstract: Zusammenfassung Nachdem Mäusen Bleiacetatlösungen intravenös eingespritzt worden waren, erhielten die Tiere Polymixin-B-Sulfat subkutan. Dies führte zu Verkalkung an der zweiten Injektionsstelle. Die histologische Untersuchung zeigte eine deutliche degranulation der Mastzellen, eine lokale Vasodilatation und das Austreten von Bleiionen aus diesen Gefäßen 24 Std nach der Injektion konnte eine groß Menge von Calcium- und Phosphationen eindeutig nachgewiesen werden. Weiter wurden Gruppen von Mäusen, die vorher Bleiacetat intravenös erhalten hatten. Bestandteile von Mastzellen-Granula injiziert. Diese bestanden aus Histaminphosphat, Serotonin-Creatinin-Sulfat, Heparin, Chondroitin-Sulfat oder Hyaluronsäure. Unter diesen exogenen Bestandteilen bewirkten nur Serotonin und Histamin eine Verkalkung. Beide sind starke Vasodilatatoren und erhöhen vermutlich die kapillare Permeabilität. Es wird postuliert, daß die Rolle der Mastzelle in der “calcergy” viel eher auf einer lokalen Vasodilatation mit erhöhter kapillarer Permeabilität als auf einer primären Bindung der Metallionen beruht.
    Notes: Abstract Mice previously injected intravenously with lead acetate solution were injected subcutaneously with Polymixin B Sulphate. This resulted in calcification at the latter injection site. Histological evidence showed marked mast cell degranulation, local vasodilation and the efflux of lead ions from these vessels. At twenty four hours after injection abundant calcium and phosphate ions were readily demonstrated. In addition, groups of mice pre-injected intravenously with lead acetate, were injected with constituents of mast cell granules. These included histamine phosphate, serotonin creatinine sulphate, heparin, chondroitin sulphate or hyaluronic acid. Of these exogenous constituents used, calcification was found only after serotonin and histamine injections, both of which are potent vasodilators and presumbly increase capillary permeability. It is postulated that the role of the mast cell in calcergy may be mainly that of producing local vasodilation with increased capillary permeability rather than the initial binding of metallic ions.
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  • 41
    ISSN: 1432-2013
    Keywords: l-Histidine Transport ; Proximal Tubule ; Transport Kinetics ; Fanconi Syndrome ; Kidney ; Microperfusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The kinetics ofl-histidine reabsorption by the proximal convolution of the rat nephron have been studied by stationary microperfusion with simultaneous perfusion of peritubular capillaries. Steady-state concentrations (C ∞) and transepithelial concentration differences (Δc ∞) were determined over a wide range of peritubular bistidine concentrations. It was found that Δc ∞ increased hyperbolically with increase in luminal and peritubular histidine concentrations suggesting saturation transport kinetics. Furthermore Δc ∞ declined linearly along the convolution suggesting that nett active transport was not constant throughout the tubule. Using an expression to describe the rate of attainment of steady-state concentration in terms of lummal and peritubular histidine concentrations, histidine permeability coefficient (P), the maximum rate of active histidine transport (J max) and the half saturation constant of the transport reaction (K m ), we were able to determine the cause of the tubule inhomogeneity. We find thatP (14.1×10−5 cm/s) andJ max (45×10−10 mol/cm2· s) are constant along the convolution but thatK m increases markedly from about 5.4 mmol/kg 26% of the way along the convolution to 40 mmol/kg at 86%. These findings suggest that the histidine reabsorptive mechanism would be relatively inefficient with histidinuria occurring at all plasma concentrations but it would have enormous reserve capacity so that saturation would not readily occur. This prediction accords with available data on histidine clearance in the rat.
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  • 42
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 343 (1973), S. 267-272 
    ISSN: 1432-2013
    Keywords: Kidney ; Lanthanum ; Tight Junctions ; Epithelia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The penetration of either “ionic” or “colloidal” lanthanum into the tight junctions of different tubular segments of the rat kidney was studied with the electron microscope. After perfusing the tracer through the aorta it was found that “ionic” and “colloidal” lanthanum penetrated the tight junctions of both the proximal and distal convoluted tubules, while the junctions of the collecting tubules were free of tracer. An attempt to correlate junctional tightness and electrical resistance in these epithelia is presented.
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  • 43
    ISSN: 1432-2013
    Keywords: Kidney ; Microcirculation ; Renal Blood Flow ; Acute Renal Failure ; Intravital High-Speed Microcinematography ; Peritubular Capillaries ; Welling Points
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The incident-light, high-frequency microcinematography of the kidney surface of rats is described as a new method for investigating renal microcirculation. The welling point area served as the anatomical reference point for microcirculatory measurements. In the first section of vessel distal to the welling point the average flow velocity was 2.32±0.24 mm/sec; the diameter was 15.91±0.92 microns. Flow rate in the efferent arteriole, calculated from the flow rate in the first vessel section distal to the welling point and the degree of ramification, was 103 nl/min. The results closely agree with total renal blood flow that was determined simultaneously. As an example for measurements taken under different conditions, a model for experimental acute renal failure was chosen. In kidneys subjected to a 60 min period of ischemia three days prior to use, the peritubular blood flow at the kidney surface was decreased only by 1/4; the difference in the means was insignificant. Therefore, a lasting cortical ischemia cannot be the only cause for the persistent oliguria in experimental acute renal failure.
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  • 44
    ISSN: 1432-2013
    Keywords: Saline Infusion ; Ultrafiltrable Calcium ; Parathyroid Gland Activity ; Ultrastructure of the Rat Parathyroids ; Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experiments have been performed in adult female rats to examine the effects of saline infusion on calcium concentration in plasma ultrafiltrate and on the ultrastructure of the parathyroids as studied with the electron microscope. Intravenous infusions of isotonic saline of at least 10 ml within 30 min decreased calcium concentration in plasma ultrafiltrate from 3.04±0.15 mEq/l to 2.79±0.11 eEq/l (P〈0.001). Saline infusions of 2 h duration at a rate of 0.5 ml/min decreased significantly the number of secretory granules in the parathyroid cells and induced considerable growth of the Golgi apparatus. It is concluded, that saline infusions in the rat decrease the ionized fraction of plasma calcium concentration thereby increasing parathormone secretion rate.
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  • 45
    ISSN: 1432-2013
    Keywords: Antihypertensive Agents ; Desoxycorticosterone ; Kidney ; Nephrectomy ; Renin ; Sodium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In rats made hypertensive by partial constriction of one renal artery and contralateral nephrectomy, large doses of furosemide had no hypotensive effect. However, when furosemide natriuresis was followed by removal of the clamped kidney, arterial blood pressure was greatly reduced. The fall of blood pressure induced in this manner was significantly correlated with the amount of sodium and water lost. The absence of a hypotensive effect of furosemide in rats with one-kidney Goldblatt hypertension appeared to be due to enhanced renin secretion. Furosemide not followed by nephrectomy caused a fall of blood pressure in rats with one-kidney Goldblatt hypertension after renin-depletion by desoxycorticosterone and salt treatment. Sodium wastage induced by peritoneal dialysis after removing the clamped kidney also lowered the blood pressure of hypertensive rats.
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  • 46
    ISSN: 1432-2013
    Keywords: Urea ; Sodium ; Kidney ; Transport ; (Na+K)-ATPase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Microsomal ATPase activity was studied in three regions of the rat kidney: cortex, medulla and papilla. (Na+K)-ATPase activity was highest in the medulla but a substantial activity, comparable to that in the cortex, was also present in the papilla. In the presence of high sodium (200–320 mM) or urea (100–900 mM) progressive inhibition of Mg-ATPase activity was observed in all three regions of the kidney. Urea (900 mM) or Na (320 mM) caused activation of (Na+K)-dependent ATPase in the medulla and inhibition of this enzymatic activity in the papilla of the kidney. Total microsomal ATPase activity in the medulla was unchanged in the presence of urea or sodium but was reduced in the papilla. Urea inhibited non-selectively Mg-p-nitrophenylphosphatase and K-activated p-nitrophenylphosphatase in all three parts of the kidney. These findings may point to a molecular basis for the function of urea and of sodium in the concentrating mechanism of the kidney.
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  • 47
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 137 (1973), S. 167-175 
    ISSN: 1432-0878
    Keywords: Leydig cells ; Mouse ; Ring-shaped nucleolus ; Endoplasmic reticulum ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Many mature Leydig cells of adult mice contain annular nucleoli. In the cytoplasm of these cells, there is an abundance of agranular endoplasmic reticulum and its modifications, i.e. membranous whorls and double-walled tubules. By contrast, the cytoplasm of Leydig cells with compact nucleoli shows abundant free ribosomes and granular endoplasmic reticulum. It is assumed that the granular endoplasmic reticulum shifts to the agranular endoplasmic reticulum and its modifications during the differentiation of the Leydig cell. For the maturation of the Leydig cell the annular nucleoli may play an important role.
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  • 48
    Electronic Resource
    Electronic Resource
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    Cell & tissue research 139 (1973), S. 201-215 
    ISSN: 1432-0878
    Keywords: Median eminence ; Mouse ; Ontogenesis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les fibres nerveuses renfermant des vésicules granuleuses et des vésicules de type synaptique apparaissent dans l'éminence médiane de foetus de 14 jours. Dés le 18è jour foetal, de véritables terminaisons nerveuses sont au contact des capillaires du plexus intercalaire, constituant une charnière neurohémale. Les anses intrainfundibulaires commencent à pénétrer dans l'éminence médiane à la naissance mais ce n'est que chez des souris de 5 jours qu'elles deviennent très nombreuses. — Nous discuterons sur des critères morphologiques, de la possibilité d'un contrôle hypothalamique sur l'adénohypophyse avant la naissance.
    Notes: Summary Nerve fibers containing granular vesicles and vesicles closely resembling synaptic vesicles appear in the median eminence of 14 days old mouse fetuses. At 18th fetal day true nerve endings have been observed which are located close to the capillaries of the superficial plexus forming a neurovascular link. The capillary loops penetrate into the median eminence at the time of parturition but only in 5 days old mice they can be observed more frequently. — On the basis of the morphological observations presented the question is discussed whether the hypothalamus can influence pituitary hormone secretion before birth.
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  • 49
    ISSN: 1432-0878
    Keywords: Subcommissural organ ; Mouse ; Mucopolysaccharides ; Acid phosphatase activities
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In mice most of the ependymal cells of the subcommissural organ (SCO cells) are densely packed with dilated cisternae of the endoplasmic reticulum (ER) containing either finely granular or flocculent materials. The well developed supra-nuclear Golgi apparatus consists of stacks of flattened saccules and small vesicles; the two or three outer Golgi saccules are moderately dilated and exhibit numerous fenestrations; occasional profiles suggesting the budding of coated vesicles and formation of membrane-bound dense bodies from the ends of the innermost Golgi saccules are seen. A few coated vesicles and membrane-bound dense bodies of various sizes and shapes are also found in the Golgi region. The contents of the dilated ER cisternae are stained with periodic acid-silver methenamine techniques. In the Golgi complex the two or three inner saccules are stained as deeply as the dense bodies, and the outer saccules are only slightly stained. The stained contents of ER cisternae are more electron opaque than those of the outer but less opaque than those of the inner Golgi saccules and the dense bodies. Acid phosphatase activities are localized in the dense bodies, some of the coated vesicles in the Golgi region, and in the one or two inner Golgi saccules. On the basis of these results the following conclusions have been reached: (1) In mouse SCO cells the finely granular and the flocculent materials in the lumen of ER cisternae contain a complex carbohydrate(s) which is secreted into the ventricle to form Reissner's fiber; (2) the secretory substance is assumed to be synthesized by the ER and stored in its cisternae, and the Golgi apparatus might play only a minor role, if any, in the elaboration of the secretory material; (3) most of the dense bodies in the mouse SCO cells are lysosomal in nature instead of being so-called dark secretory granules.
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  • 50
    ISSN: 1432-0878
    Keywords: Intercellular junctions ; Neonatal liver ; Mouse ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Au cours du passage de la vie foetale à la vie postnatale, on note, dans le foie de souris, l'apparition d'associations jonctions-organites cellulaires. Celles-ci cont de deux types: associations desmosomes-organites et associations nexus-organites. 1.Associations nexus-organites. Le long de la «gap junction» sont étroitement accolés, uni ou bilatéralement, divers organites: mitochondrie(s), subsurface cisterna(e), peroxysome(s) ou lysosome. Ces associations n'apparaissent qu'entre le 21ème jour de la gestation et le ler jour post-natal, période à partir de laquelle ils disparaissent au profit d'associations desmosomes-organites cellulaires. Un nouveau type de structure s'associe dans le foie aux membranes plasmatiques: il s'agit des saccules ergastoplasmatiques ou subsurface cisternae. 2.Associations desmosomes-organites. Dans ces complexes, les tonofilaments desmosomiques entrent étroitement en contact avec la paroi des organites cellulaires associés: mitochondrie ou peroxysome. Déjà présents au 13ème jour de la gestation, ces structures s'observent plus fréquemment à partir du ler jour post-natal. La signification de ces associations reste à déterminer, d'autant plus que leur présence a déjà été signalée dans de trés nombreux tissus. Quelques hypothèses sont présentées.
    Notes: Summary During the transition between the fetal and postnatal periods associations between cell junctions and cell organelles appear in the liver of the mouse. These associations are of two types: desmosome-organelle and nexus-organelle. 1.Nexus-Organelles Association. Unilaterally or bilaterally, various organelles — mitochondria, cysternae, microbodies or lysosomes — adhere tightly along the gap. These associations appear only between the 21st day of gestation and the first postnatal day. Thereafter they gradually disappear and are replaced by desmosome-organelle associations. Another type of structure — ergastoplasmic saccules or cisternae of rough endoplasmic reticulum — become associated with the cell membrane. 2.Desmosome-Organelle Associations. In these complexes the desmosomal microfilaments are in close contact with membranes of the associated organelles — mitochondria or peroxysomes. The associations, which exist as early as the 13th day of gestation increase after the first postnatal day. The significance of these associations remains to be ascertained, especially since they occur in many other tissues. A few hypotheses are presented.
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  • 51
    ISSN: 1432-0878
    Keywords: Kidney ; Contractile structures ; Embryonic metanephros ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cytoplasmic filaments have been observed in the cells of normal and pathological kidneys. These filaments are usually grouped into bundles anchored to electron dense bodies underlying the cell membrane. In the embryonic human metanephros the filaments are found within the cells of different portions of the nephron at various stages of development. They appear first in the podocytes, almost simultaneously in the Bowman's capsule and tubular cells, then in the “mesangial cells”, and finally in the cells of the media of the afferent glomerular and interlobular arterioles. The presence of filaments and their attachment bodies in the mammalian nephron suggests that the podocytes and the so-called mesangial cells have a contractile activity, thus representing an intraglomerular apparatus which regulates the intravascular pressure, blood flow and filtration rate in the glomerular capillaries, whilst the contractile activity of the Bowman's capsule and proximal, distal, and collecting tubules, could facilitate the progression of the filtrate. The increase in number of the filaments in some pathological conditions is probably related to the functional changes of the intraluminal pressure in the glomerular capillaries, in the Bowman's space, and in the tubular lumen.
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  • 52
    ISSN: 1432-0878
    Keywords: Kidney ; Sexual accessory organs ; Reptiles ; Secretion ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Kidneys of adult male and female lizards were studied by electron microscopy, in order to understand the ultrastructure of the collecting duct and a differentiated part thereof, the sexual segment, which is an important accessory sexual organ. First portion of sexual segment in males: The cells are filled with large secretory granules of a wide range of opacities. The granular endoplasmic reticulum is abundant; basal formations of superimposed flat cisternae are frequent. Distended vesicles and microvesicles prevail in the supranuclear, well developed Golgi apparatus. Evidences indicate that secretion of these cells is holocrine. Second portion of sexual segment in males: All of the secretory granules are apical in location and relatively electron-opaque; they show a denser core. This core is formed by a substance which, after lying in contact with ribosomes, enters the secretory vesicles of the highly developed Golgi apparatus. A lighter substance is then condensed around it. The secretion of the granules is merocrine. The granular endoplasmic reticulum is very abundant in these cells, but basal ergastoplasmic formations are lacking. Sexual segment in females: The cells show features similar to those of the male first portion, but they are smaller. Undifferentiated collecting duct: Most of the cells are mucigenic. They have small ovoid, apical secretory granules. The density of the granules varies from cell to cell; when they are electron-lucent, they exhibit laminar or dotted opaque figures. Moderately developed Golgi apparatus and granular endoplasmic reticulum, as well as elongated mitochondria, occur in mucigenic cells. Intercalated among the latter are non-secretory cells. They have very abundant mitochondria, numerous microvilli, many pinocytic and smooth-membrane vesicles, whereas the organelles participating in synthetic processes are poorly developed; their function is most likely related to active solute transport.
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  • 53
    ISSN: 1432-0878
    Keywords: Hypothalamus ; Mouse ; Arcuate neurons ; Nucleolus-like bodies ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The arcuate nucleus of untreated (control) and castrated adult mice was studied with the electron microscope. Nucleolus-like bodies (NLB) were found in the cytoplasm and occasionally in the dendrites of arcuate neurons. NLB were spherical or ovoid, 0.7–1.5µm in diameter; they were composed of granules 100–150 Å and 200 Å in diameter, and filaments ∼70 Å in diameter. NLB were frequently associated with free ribosomes and cisternae of the rough endoplasmic reticulum. Light microscopic studies with basic dyes and enzymatic digestions showed that these bodies contained some RNA. There was no significant change in the number of NLB in castrated animals.
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  • 54
    ISSN: 1432-0878
    Keywords: Vaginal epithelium ; Cell differentiation ; Mouse ; Estradiol sensitive antigen ; Immunocytology, Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of an antigenic material specific for the cervicovaginal epithelium (CVA) was studied in the vaginal epithelium of the adult mouse with immunofluorescence and immunoferritin techniques. The antigen localization has been correlated to the fine structure of the vaginal epithelium in various states of functional activity. The antigen distribution in adult ovariectomized mice and in ovariectomized mice treated with estradiol was compared with that in normal cycling mice. CVA was found to be associated with the exterior of the cell membrane of vaginal epithelium cells, being part of the glycocalyx. Two cell types, mucous or keratinized, are derived from the germinative cell layer of the vaginal epithelium, depending on the hormonal environment. Mucous cells with morphological features that characterize cells about to cornify have been demonstrated. Fluorescence as well as ferritin particles, indicating the presence of antigen-antibody complexes, were seen within the mucous droplets of the mucous cells. The CVA production is apparently connected with vaginal mucus formation. The CVA distribution in the adult vaginal epithelium is discussed in relation to the distribution demonstrated earlier in the cervicovaginal epithelium of neonatal mice.
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  • 55
    ISSN: 1432-0878
    Keywords: Kidney ; Bufo bufo ; Juxtaglomerular apparatus ; Macula densa ; Light Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In a light microscopic study the course of the tubule in the kidney of the toadBufo bufo was studied. The distal tubule returning to the glomerulus of its origin appears to enclose the afferent arteriole. In that area, from which a three dimensional graphic reconstruction is made, there is an intimate contact between tubular and vascular wall. The latter contains granulated media cells. In the part of the tubule adjacent to the afferent arteriole an accumulation of nuclei is present. It is suggested that this structure is similar to the macula densa of the mammalian juxtaglomerular apparatus. The functional significance of a stricture in the tubule distally from the macula densa-like structure is discussed.
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  • 56
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 140 (1973), S. 445-449 
    ISSN: 1432-0878
    Keywords: Cecum, Colon ; Mouse ; Glycocalyx ; Intestinal microorganisms ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the cecal epithelium of the mouse resembles that of more distal parts of the colon. A brief discussion is presented of the possible significance of apical cytoplasmic granules to the glycocalyx and of the close association of microorganisms with the lining epithelium.
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  • 57
    ISSN: 1741-0444
    Keywords: Kidney ; simulation ; analogue ; water reabsorption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Sommaire Cette communication décrit une simulation de calcul analogique du contrôle de l'osmolalité du sang au moyen du transfert d'eau à partir du tubule cortical et du tube collecteur, à travers la région médullaire, jusqu'aux vaisseaux droits. Quand la simulation est sujette aux tests séparés d'ingestion d'eau et d'injection de saline, elle produit des résultats réalistes, quand on les compare aux enregistrements de tests semblables sur l'homme et sur les animaux expérimentaux. Pour parvenir à un fonctionnement général satisfaisant de la simulation, il a été nécessaire d'inclure des facteurs qui soient compatibles avec un rôle double pour l'h.a.d. Dans le modèle, l'effect de l'h.a.d. n'est pas seulement de changer la perméabilité de l'épithélium tubulaire, mais aussi d'altérer la vitesse de l'afflux du sang et la pression hydrostatique dans les vaisseaux droits.
    Abstract: Zusammenfassung Dieser Aufsatz beschreibt die Simulation durch einen Analog Computer der Kontrolle von Blutosmolalität, mit Hilfe der Wasserübertragung von dem distal tubulus und Sammelgang durch das Mark zum vasa recta. Diese Simulation, wenn sie getrennten Testen von Wassereinnahme und Salzinjektion unterzogen ist, bringt realistische Resultate wenn man sie mit den Ergebnissen ähnlicher Versuche an Menschen oder Versuchstieren vergleicht. Um eine in allen Punkten befriedigende Simulation zu bekommen, war es notwendig, Faktoren einzubeziehen, die mit einer Doppelrolle für a.d.h. übereinstimmen. In dem Modell ist der Effekt von a.d.h. nicht nur dazu da, um die Durchlässigkeit des tubular epithelium zu ändern, sondern er verändert auch die Blutströmungsge-schwindigkeit und den hydrostatischen Druck in der vasa recta.
    Notes: Abstract This paper describes an analogue-computer simulation of the control of blood osmolality by means of water transfer from the distal tubule and collecting duct through the medulla to the vasa recta. The simulation, when subject to the separate tests of water ingestion and saline injection, produces realistic results when compared with the records of similar tests on humans and on experimental animals. To achieve the satisfactory overall performance from the simulation, it was necessary to include factors which are consistent with a dual role for a.d.h. In the model, the effect of a.d.h is not only to change the permeability of the tubular epithelium, but also to alter the blood-flow rate and hydrostatic pressure in the vasa recta.
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  • 58
    ISSN: 1432-0878
    Keywords: Kidney ; Male rat ; Proximal tubule segments ; Electron microscopy, cytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pars descendens (pars recta) of the proximal tubule in the male rat kidney, consisting of the terminal part of the second proximal segment (P2) and of the third proximal segment (P3), was studied with the electron microscope. A technique of tissue orientation and trimming was used which permitted precise topographic definition of the tubules studied in the electron microscope. The terminal descending part of the P2 showed some minor differences from the convoluted part of this segment, and ultrastructure also changed along the course of the P3. In the beginning of the latter segment numerous, shallow interdigitations were observed between adjacent cells; along the course of the segment they decreased in number or disappeared. In the initial part of the P3 mitochondria were more abundant than in the terminal portion of the segment and at least as numerous as in the straight part of the P2. Also, the dense, acid phosphatase-positive cytoplasmic bodies decreased somewhat in size along the course of the P3. The smooth surfaced endoplasmic reticulum reached a higher development in the P3 than anywhere else in the proximal tubules.
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  • 59
    ISSN: 1432-0878
    Keywords: Ovum ; Mouse ; Membranes ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural studies have revealed the presence of unusual membrane complexes within developing mouse oocytes. These structures, most obvious 18 days post fertilization, are found in the nucleus or cytoplasm of cells in meiotic prophase. The complexes, usually found in small groups, are characterized by a slightly bowed appearance, and a thin middle section that is vesiculated at each end. At high magnification the middle section exhibits a pentalaminar structure similar to tight junctional complexes, while the looped membranes of the vesiculated ends are trilaminar in appearance. In addition to being free in the nucleoplasm or cytoplasm, the complexes are also seen in continuity with the inner and outer leaflets of the nuclear envelope, and with typical membranes forming cytoplasmic tubular systems. The possible formation of these complexes from blebs or vesicles derived from the nuclear envelope is presented and the role that these structures may play in developing oocytes is discussed.
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  • 60
    ISSN: 1432-0878
    Keywords: Juxtaglomerular cells ; Kidney ; Teleost (Gasterosteus) ; Migration ; Kidney structure ; Morphometry
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