Question

When does detumescence occur? Describe the nervous control and what occurs to facilitate this event.

Answer 1

Detumescence is the reversal of Tumescence,(state of swelling) by which blood leaves the erectile tissue, returning the erectile tissue to the flaccid state. Stimulation of the sympathetic trunk causes detumescence, it occurs through thoracolumbar segments in the spinal cord, Detumescence occurs when there is stopage of neurotransmitter release, breakdown of second messengers by phosphodiesterase, and sympathetic nerve excitation during ejaculation. Contraction of the smooth muscle of the pen!s and contraction of the penile arteries lead to a decrease of blood in the lacunar spaces and contraction of the smooth trabecular muscle leads to a collapse of the lacunar spaces and reopens the venous channels which allow the blood to be expelled out and thereby causing flacidity as a result detumescence occurs.