비아그라의 가장 좋은 측면 VIAGRA

Sexual stimulation that contributes to an erection causes the manufacturing and launch of nitric oxide in the penis. Nitric oxide leads to an enzyme, guanylate cyclase, to make cyclic guanosine monophosphate (cGMP) that is mostly to blame for growing and decreasing the size of blood vessels carrying blood to and from your penis and creating an erec