Erection
The vasodilatatory effect of NO, in turn, also plays a role in development and maintenance of erection. Vasodilation of blood vessels supplying the corpus cavernosum results in more blood flowing in and hence erection. This is the biological basis of sildenafil (Viagra), which works to inhibit the enzyme phosphodiesterase PDE5 that lowers the cGMP concentration by converting it back to GMP.
Read more about this topic: Biological Functions Of Nitric Oxide