비아그라에 대한 5가지 쉬운 사실 설명

Sexual stimulation that contributes to an erection brings about the generation and launch of nitric oxide during the penis. Nitric oxide results in an enzyme, guanylate cyclase, to supply cyclic guanosine monophosphate (cGMP) that is definitely mainly to blame for increasing and decreasing the size of blood vessels carrying blood to and from your p

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