비아그라에 대해 알려지지 않은 사실

Sexual stimulation that brings about an erection leads to the production and launch of nitric oxide within the penis. Nitric oxide results in an enzyme, guanylate cyclase, to generate cyclic guanosine monophosphate (cGMP) that is definitely principally liable for rising and reducing the scale of blood vessels carrying blood to and with the penis an