Urination is periodically coming reflex act of emptying the bladder. The regulatory role of the nervous system in the act of urination is near reflexes. Directly in the act of urinating participate smooth muscle of the bladder and urethra. The disclosure cervix bladder during urination occurs not on the relaxation of the internal sphincter, and in connection with the reduction of muscles of the bladder. In a healthy person, feeling the urge to urinate occurs when a cluster in the bladder 100-150 ml of urine; sharp degree this feeling gets when a cluster of 350-400 ml of urine. These figures are subject to some individual fluctuations. Volitional healthy person is able to suppress the feeling of urge and delay urination.
Painful, difficult and frequent urination (dysuria) occurs as a result of diseases of the Central nervous system, urinary bladder, urethra and prostate gland (see Isoria, urinary Incontinence).
For a number of diseases cannot complete emptying of the bladder, is the so-called delay of urine. Depending on the reason there are two main forms of urinary retention - mechanical, for which there obturation lower divisions urinary tract, and neurogenic, caused by defeat of the Central or peripheral nervous system; organic changes in the lower urinary tract in this form of urinary retention missing.
Urinary retention may be acute (full), occurring suddenly and chronic (partial, incomplete), is developing gradually. If chronic urinary retention urination occurs independently, but the bladder is emptied incomplete (there is a residual urine). In cases where time does not eliminated reasons for the delay urine, can develop a paradoxical esure (see).
Treatment of urinary retention - see table including 3 (Applications).