비아그라에 대한 새로운 단계별 지도

Sexual stimulation that results in an erection triggers the manufacturing and release of nitric oxide in the penis. Nitric oxide results in an enzyme, guanylate cyclase, to generate cyclic guanosine monophosphate (cGMP) that may be principally to blame for escalating and decreasing the scale of blood vessels carrying blood to and from your penis an