The physiology and pharmacology of the lower urinary tract

Abstract

The lower urinary tract consists of the urinary bladder, the urethra, and the prostate in males. The primary function of the lower urinary tract is to store and voluntarily release urine. During the urine storage phase the bladder wall distention activates stretch receptors. The bladder's compliance ensures urine storage without a significant increase in the intravesical pressure. The sympathetic nervous system maintains the bladder relaxed and the internal sphincter contracted. The external sphincter is under voluntary control and prevents urination. The central nervous system regulates and suppresses the micturition reflex. This coordinated control allows the safe storage of urine until the appropriate time for urination arrives. Pathologies affecting any of these levels result in a range of lower urinary tract symptoms, leading to prevalent symptoms that can significantly affect the patient's quality of life. Pharmacological treatment aimed at alleviating these symptoms contributes to enhancing urinary function and to improving the quality of life.