비아그라에 대한 사실 아무도 제안하지 않는다

Sexual stimulation that brings about an erection triggers the production and launch of nitric oxide during the penis. Nitric oxide leads to an enzyme, guanylate cyclase, to make cyclic guanosine monophosphate (cGMP) that's principally answerable for rising and decreasing the size of blood vessels carrying blood to and from your penis and resulting