[New physiological aspects of the human urinary bladder (author's transl)].

With respect to the new electrophysiological, morphological, histochemical, pharmacological and urodynamical investigations of the function of the urinary bladder, the common aspect of the existence of a smooth sphincter on one hand and a striated sphincter on the other hand, an alternate function of the parasympathetic and sympathetic nervous system in filling of the bladder and in micturition can no more be accepted. A new own concept of the mechanism, which is in action at the bladder neck closure, is demonstrated. This concept goes out from the existence of two systems of smooth musculature in the outlet of the bladder. The first one with mainly longitudinally laying strips is standing under parasympathetic control. Its activation in the beginning of voiding opens the bladder neck. The second one consists of more circulary strips. Its activation is alpha-adrenergic. The contraction of this part of the musculature causes the closure of the bladder neck. Certainly the striated musculature does not play an important role of the continence in normal persons resting conditions. However, in some pathological conditions, it must be taken into consideration. It must be noted, too, that the striated urethral musculature and the pelvic floor do not act synchronous.