Springer Online Journal Archives 1860-2000
Summary The viscoelastic behaviour of segments of ureters from dogs and guinea pigs has been studied by an ergometer. Elongation of the ureter produces a force, which may be ten times greater than the force of ureteric contractions, and which is proportional to the rate and magnitude of the stretch. Elongations of sufficient length and rate induce spontaneous contractions, the amplitude of which is proportional to the extent of the stretch after some cycles of elongation and shortening. The ureter shows hysteresis so that the loops of the force-length diagrams run in a clockwise direction. However, strain cycles of less than 4% LO, and less than 0.07 Hz, provoke counterclockwise loops. The loops of the force-length diagram of the contractions also slope in a counterclockwise direction. The ureter behaves like a plasto-elastic body and adapts to strain. The plastic element is at least partly due to the musculature, since the deformation is reduced by continous stimulation of the ureter.
Type of Medium: