Editing Normal Erectile Physiology (section)

==== '''Others''' ====
*'''Neurotransmitters that promote sexual function: dopamine, acetylcholine, oxytocin, and serotonin (5-HT)'''
** '''Acetylcholine contributes indirectly to penile erection''' by presynaptic stimulation of NO release from endothelial cells and inhibition of adrenergic neurons which decreases the release of norepinephrine
* '''Norepinephrine is the principal neurotransmitter mediating flaccidity'''
** α-Adrenergic nerve fibers and receptors are present in cavernous trabeculae and surrounding the cavernous arteries.
* '''GABAb receptors inhibit erectile function'''
* '''Prostaglandin E1 is erectogenic''', intracavernous injection of PGE1 is one of the safest and most effective treatments for ED
* Sonic hedgehog has been identified in the penis; inhibition of SHH in adult rats leads to rapid atrophy and disorganization of the corpus cavernosum. SHH has been shown to stimulate the expression of vascular endothelial growth factor (VEGF) and NOS in the penis
* '''Cannabinoid CB1''' receptor activation '''inhibits''' '''sexual function''' by modulating the paraventricular oxytocinergic neurons, which mediate erection. Antagonism of CB1 receptors in the PVN of male rats induces penile erection