아무도 제안하지 않는 비아그라에 대한 사실

Sexual stimulation that results in an erection will cause the production and launch of nitric oxide in the penis. Nitric oxide leads to an enzyme, guanylate cyclase, to create cyclic guanosine monophosphate (cGMP) that is definitely primarily liable for raising and lowering the size of blood vessels carrying blood to and from your penis and leading