Abstract
Nitrergic nerves and sinusoidal endothelial cells represent important sources of nitric oxide (NO) in the penis. Upon NO release, the cavernosal smooth muscle relaxes due to increases in intracellular cGMP. The levels of cGMP are controlled by both its rate of synthesis caused by stimulation of soluble guanylyl cyclase and its degradation by phosphodiesterases (PDEs). Alterations in NO-cG…