See Also: proximal urethral sphincter(medicine)
internal urethral sphincter(medicine)
external urethral sphincter(medicine)
preprostate urethral sphincter(medicine)
External urethral sphincter muscle(health)
Herbal medicine (botanical medicine, herbology, phytomedicine)(health)
Proximal(health)
proximal(dictionary)
Proximal(medicine)
proximal caries(medicine)

proximal urethral sphincter (medicine)


proximal urethral sphincter -->
sphincter vesicae


The complete collar of smooth muscle cells of the neck of the urinary bladder which extend distally to surround the preprostatic sportion of the male urethra. There is not a comparable structure in the neck of the femoral bladder; the internal urethral sphincter may exist to prevent reflux of semen into bladder.

Synonym: annulus urethralis, internal urethral sphincter, musculus sphincter vesicae, preprostate urethral sphincter, proximal urethral sphincter, sphincter muscle of urinary bladder.