The detrusor muscle is the main component of the urinary bladder and its principal function is to contract and relax to control the bladder function. The muscle remains relaxed during the urine storage process and contracts to release urine during micturition.
The muscle is related to the urethral sphincter muscles, which surround the urethra. A common problem of the detrusor muscle is overactive bladder syndrome, which is due to the involuntary contractions of the detrusor. The muscle cells in the detrusor muscle are smooth and similar in structure with the other muscular cells in the body. The muscle has a prostate insertion in males and a vaginal insertion in females.