BlasenmuskulaturVerkürzung

Blasenmuskulatur refers to the muscular wall of the urinary bladder. This muscle, known medically as the detrusor muscle, is primarily responsible for the bladder's ability to store and expel urine. It is a smooth muscle, meaning its contractions are involuntary and controlled by the autonomic nervous system.

During the filling phase of the bladder, the detrusor muscle remains relaxed, allowing the bladder to expand and hold increasing volumes of urine. This relaxation is mediated by sympathetic nerve signals. When the bladder reaches a certain fullness, signals from the parasympathetic nervous system trigger contraction of the detrusor muscle. This contraction increases the pressure within the bladder, forcing urine downwards and out of the body through the urethra.

The coordinated action of the detrusor muscle and the urethral sphincters is crucial for maintaining continence, the ability to control urination. The internal urethral sphincter, also made of smooth muscle, is normally contracted to prevent urine leakage. Upon sensing bladder fullness and initiating the urge to urinate, the detrusor muscle contracts while the internal urethral sphincter relaxes. The external urethral sphincter, composed of skeletal muscle, can be voluntarily controlled to delay urination until an appropriate time and place. Dysfunction of the blasenmuskulatur can lead to various urinary issues, including incontinence, urgency, and difficulty emptying the bladder.