Cells in corpus cavernosum produce NO during sexual arousal (NANC transmission).

Nitric oxide stimulates formation of cGMP, relax smooth muscle of corpus cavernosum and penile arteries

 engorgement of the corpus cavernosum, and erection

The accumulation of cGMP is enhanced by sildenafil which inhibit cGMP specific PDE5 (phosphodiesterase-5).

Prevention – No sildenafil to patients taking nitrates; No nitrates within 24 hrs after sildenafil.

interesting

haha