What muscle controls the urethral sphincter?
A layer of muscle called the urogenital diaphragm supplies support for the contents of the pelvis and acts as the external urethral sphincter. It provides a second means of stopping the escape of urine from the body. This sphincter is under voluntary control.
What controls the detrusor muscle?
The detrusor muscle is under autonomic control. The parasympathetic nervous system stimulates the muscarinic stretch receptors in the bladder through the pelvic nerve fibers. At the same time, the parasympathetic fibers inhibit the internal urethral sphincter, which causes relaxation allowing for bladder emptying.
What is the urinary sphincter controlled by?
It is controlled by the deep perineal branch of the pudendal nerve. Activity in the nerve fibers constricts the urethra. The internal sphincter muscle of urethra: located at the bladder’s inferior end and the urethra’s proximal end at the junction of the urethra with the urinary bladder.
What reflex controls the bladder muscle and sphincter?
Throughout bladder filling, the parasympathetic innervation of the detrusor is inhibited and the smooth and striated parts of the urethral sphincter are activated, preventing involuntary bladder emptying. This process is organized by urethral reflexes known collectively as the ‘guarding reflex’.
What muscle controls your bladder?
Sphincter muscles surround the urethra and keep it closed to hold urine in the bladder. If the nerves to the sphincter muscles are damaged, the muscles may become loose and allow leakage or stay tight when you are trying to release urine.
What is the Bulbospongiosus muscle?
The bulbospongiosus muscle acts to expel remaining urine from the urethra after the bladder has completed its emptying. In males it also aids in the final stages of erection by compressing the veins within the bulb of the penis to maintain tumescence.
What is the muscle that controls the bladder?
What nervous system controls the bladder?
The sympathetic nervous system regulates the process of urine storage in the bladder. In contrast, the parasympathetic nervous system controls bladder contractions and the passage of urine. The somatic efferent system permits voluntary control over the external periurethral sphincter.
What muscle controls the bladder?
Is the detrusor muscle under voluntary control?
The detrusor is the smooth or involuntary muscle of the bladder wall. The urethral muscles consist of the external and internal sphincter. The internal sphincter and detrusor muscle are both under autonomic control. The external sphincter, however, is a voluntary muscle under the control of voluntary nerves.
What is detrusor reflex?
Micturition or urination is the process of emptying urine from the storage organ, namely, the urinary bladder. The detrusor is the smooth or involuntary muscle of the bladder wall. When the bladder is distended it sends signals to the brain, which is perceived as the ‘full bladder’ sensation.
Does your bladder have a sphincter muscle?
The bladder sphincter is made up of two muscles, the internal and external sphincter muscles. The internal sphincter muscle is located at the opening of the bladder to the urethra. It is a smooth, involuntary muscle. Because of its location, it is also primary muscle prohibiting the release of urine.
How is the detrusor muscle and urethral sphincter controlled?
The bladder is controlled by the central nervous system. The smooth muscles (i.e. the detrusor muscle and the internal urethral sphincter) are controlled by the two different divisions of the autonomic nervous system. The parasympathetic nervous system stimulates the detrusor muscle to contract, causing the person to urinate.
What causes the contraction of the detrusor muscle?
When urine fills the bladder, the M3 receptors located within the bladder become stretched and stimulated, which leads to the contraction of the detrusor muscle for urination. At the same time, the parasympathetic fibers inhibit the internal urethral sphincter, which causes relaxation allowing for bladder emptying.
What causes the relaxation of the bladder detrusor muscle?
When the bladder empties of urine, the stretch fibers become inactivated, and the sympathetic nervous system is stimulated to activate the beta-3 receptors through the adenylyl cyclase-cAMP pathway in the bladder. This process is achieved via the hypogastric nerve, causing relaxation of the detrusor muscle.
Is the detrusor muscle part of the autonomic system?
The combination of detrusor contraction and urethral sphincter relaxation leads to urination. The detrusor muscle is under control from the autonomic system and is composed of smooth muscle. Detrusor muscle pathology can lead to urinary retention, incontinence, or a combination of both.