micturációs

Micturition is the process by which urine is expelled from the body. It is also commonly referred to as urination or voiding. This complex physiological act involves the coordinated function of the urinary bladder, the urethra, and the nervous system.

The bladder, a muscular organ, stores urine produced by the kidneys. As the bladder fills, stretch receptors in its wall are activated. These receptors send signals to the brain, creating the sensation of needing to urinate. When the decision to void is made, the brain signals the detrusor muscle, the smooth muscle of the bladder wall, to contract. Simultaneously, the internal and external urethral sphincters, which normally remain closed to prevent leakage, relax.

The contraction of the detrusor muscle increases the pressure within the bladder, forcing urine through the relaxed sphincters and out of the body via the urethra. This entire process is under voluntary and involuntary control. The voluntary control allows individuals to initiate or delay urination, while involuntary mechanisms ensure continence during normal daily activities. Disruptions to any part of this system can lead to various micturition disorders.