Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1432-2072
    Keywords: Social play ; Opioid ; Morphine Environment ; Social isolation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To clarify the influence of opioids on social play, the effects of morphine on playful and non-playful social behavior in juvenile rats was investigated under different conditions. Environmental variables employed were different (dim and intense) levels of illumination during testing, familiarity to the test cage, and different periods of social isolation prior to testing. Under dim light conditions, morphine markedly increased playful social behavior, such as pinning, boxing/wrestling and following/chasing, whereas non-playful social behavior such as social exploration and contact behavior was hardly affected. This effect of morphine was independent of duration of previous isolation and dose-dependent, with a maximal effect at 1.0 mg/kg. The mechanism of this effect is interpreted as an action on the rewarding aspects of play. A dose of 0.1 mg/kg of morphine abolished the initial suppression of play induced by unfamiliarity to the test cage, without influencing total levels of play. This may be an effect of morphine on the integration of sensory stimuli. Under intense light conditions, where playful behavior was completely suppressed, morphine itself hardly affected such behavior, but decreased some aspects of non-playful social behavior. These results suggest that in juvenile rats playful and non-playful forms of social behavior are differentially regulated. In addition, opioid systems may be involved at different levels in the regulation of social play.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1439-6327
    Keywords: Key words Cytoplasmic fatty acid-binding protein ; 3-Hydroxyacyl-coenzyme A dehydrogenase ; Citrate synthase ; 6-Phosphofructokinase ; Endurance training
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effect was investigated of treadmill training of moderate intensity on the fatty acid-binding protein (FABP) content in relation to parameters of oxidative and glycolytic metabolism. To this end, the cytoplasmic FABP content and the activity of β-hydroxyacyl-coenzyme A dehydrogenase (HAD), citrate synthase (CS), and 6-phosphofructokinase (PFK) were measured in heart, fast-twitch extensor digitorum longus (EDL) and slow-twitch soleus muscles (SOL) of male Wistar rats. To investigate the influence of the amount of training (defined as the product of exercise duration, intensity and frequency), two training groups were created that differed in training frequency (HF, high frequency 5 days · week−1, n=9; LF, low frequency 2 days · week−1, n = 9; the exercise being 20 m · min−1 for 2 h with no gradient, over 6 weeks) and compared with SC, sedentary controls (n = 7). In heart muscle, the cytoplasmic FABP content was 34% higher in HF than in SC but was the same as in LF. The CS and HAD activities were no different in the three groups, suggesting that the capacity to oxidize fatty acids (FA) was not affected by training. The PFK activity was higher (43%) in HF, suggesting a shift towards carbohydrate utilization. The FABP content and HAD activity did not change in SOL and EDL after training whereas the CS activity increased (27%) in SOL and decreased (21%) in EDL in both training groups. In addition, PFK activity in EDL was much higher (113%) in the HF than in SC group. The HF training was associated with a fine-tuning of FA availability and use in heart muscle, and with a more efficient energy production. It is suggested therefore that cytoplasmic FABP could be an early marker of muscle adaptation to training in heart but not in skeletal muscle. The training reinforced the metabolic profile of the skeletal muscles, in particular that of the fast-twitch glycolytic muscle. We concluded that a large amount of training is needed when the effect on both oxidative and glycolytic parameters is to be studied.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-6792
    Keywords: 1H-NMR imaging ; (Rat) brain ; Fimbria fornix ; Hippocampus ; Ventricle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Mechanical lesions of the fimbria fornix (FF) have been widely used as a model to investigate the recovery of damaged brain tissue.1H-NMR imaging was employed to non-invasively measure changes in the brain after unilateral FF transection. Rats were subjected to NMR imaging at various times after the lesions were made. The experimental protocol included (multislice) T2-weighted and diffusion-weighted imaging thereby allowing the construction of two-dimensional maps of the relaxation time T2 (transverse or spin-spin relaxation time) and the apparent diffusion coefficient (ADC) of water. FF transection induced considerable changes in the status of the brain tissue at a number of different locations which were exclusively present in the affected hemisphere. At 1 day post-lesion the region of the lateral ventricle and hippocampus started to display pronounced changes in that T2- and diffusion-weighted images showed a hyperintensity and a hypointensity, respectively. These effects were maximal around day 2 to 4 whereafter a slow recovery towards the control situation was observed. Immediately after transection the FF lesion itself could be visualized. These early images pointed to an aspecific disruption of the tissue due to the mechanical intervention. Interestingly, however, from day 2 post-lesion a number of changes became evident in this region which seemed to be localized to specific structures, including the ventricle and hippocampus. After one month the presumably ventricular effect dominated and was predominantly localized to the anterior side of the FF lesion. These findings are indicative of pronounced changes in the status of water (e.g., in its distribution between extra- and intracellular compartments) at a number of locations distant from the site of FF transection. The mechanism by which these changes are brought about and the origin of their time-dependence remain to be elucidated.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...