Virtsanerittyminen

Virtsanerittyminen, also known as urination or micturition, is the process by which urine is expelled from the body. It is a vital physiological function controlled by both the nervous and muscular systems.

The process begins with the kidneys filtering waste products and excess water from the blood, forming urine. This urine then travels down the ureters to the bladder, a muscular sac that stores it. As the bladder fills, stretch receptors in its walls send signals to the brain, creating the sensation of needing to urinate.

When the decision to urinate is made, the brain signals the bladder muscles to contract and the sphincter muscles at the base of the bladder to relax. This coordinated action allows urine to flow out of the body through the urethra.

Several factors can influence virtsanerittyminen, including fluid intake, diet, certain medications, and underlying medical conditions. Conditions like urinary tract infections, overactive bladder, and prostate issues can disrupt normal urination patterns, leading to symptoms such as increased frequency, urgency, or difficulty emptying the bladder. Maintaining adequate hydration and a healthy lifestyle generally supports normal urinary function.