Good morning again,
So one of the things that I have always wondered is how does Viagra work? How did it achieve its function in men. So I went and did a little research and I came up with this:
Viagra was intentionally meant for men who suffered from erectile dysfunction. For examples many diabetes suffer from erectile dysfunction especially pass the age of 45. So what happens is that when a man is aroused and this causes the release of Cyclic Guanosine Monophosphate in the body. These chemicals will relax the muscles of the penis and allow large amounts of blood to enter the penis. Normally blood can not flow to the penis as the blood flow is cut off by constricted muscles. So once these muscles are relaxed blood flows into the penis and allows an erection to take place. The erection is normally reversed by the release of a chemical known as phosphodiesterase type 5 [PDE5]. This chemical breaks down Cyclic Guanosine Monophosphate (stucture is below) which allowsthe muscles to relax. The muscles in the penis will constrict again and blood will leave the penis.
Now viagra works by blocking PDE5. When PDE5 is blocked the chemicals which are responsible for the relaxation of muscles (Cyclic Guanosine monophosphate) are not broken down and hence the penis remains in an erected state for a longer period of time. This has been proven very useful for the male population.