urethral sphincter

Function

• the segment of the urethra that influences storage & emptying of urine in the bladder
• it controls bladder voiding by relaxing, which opens the outlet from the bladder, allowing urine to flow from the bladder to the outside of the body
• the urethral sphincter contracts in response to alpha-adrenergic stimulation via hypogastric plexus (T11-L2).

Pathology

• a deficiency of the urethral sphincter mechanism may allow leakage of urine in the absence of a detrusor contraction

More general terms

• urogenital system structure

More specific terms

• internal urethral sphincter (preprostatic or supracollicular sphincter, preprostate or proximal urethral sphincter, sphincter muscle of urinary bladder)
• urethrovaginal sphincter

Component of

• urethra