A Simple Introduction of Sildenafil

   Sildenafil citrate ,which is sold as Viagra, Revatio and under various other trade names, is a drug used to treat erectile dysfunction and pulmonary arterial hypertension. It was originally developed by British scientists and then brought to market by the US-based pharmaceutical company Pfizer. Sildenafil  works by inhibiting cGMP-specific phosphodiesterase type 5, an enzyme that promotes degradation of cGMP, which regulates blood flow in the penis. Sildenafil has been the prime treatment for erectile dysfunction since becoming available in 1998 and its primary competitors on the market are tadalafil and vardenafil.

Type 5 phosphodiesterase (PDE5) is the role of target of sildenafil, the phosphodiesterase is a negative regulator of the NO-cGMP pathway to reduce the role of nitric oxide by the decomposition of the catalytic cGMP is generally believed thatthe body's Nitric oxide is a regulator of vascular smooth muscle expansion factor, thus the role of phosphodiesterase in vascular smooth muscle contraction.

Sildenafil can be highly selective inhibition of PDE5 activity in vivo, of PDE5 in the corpus cavernosum of the expression level is extremely high and low expression in other body tissues and organs. Sildenafil, the corpus cavernosum vascular smooth muscle relaxation under the influence of drugs, blood flow increases, the cavernous congestion, penile erection, resulting in the treatment of erectile dysfunction.

The clinical trials show that people in the Europe and the United States, about 78% of subjects taking sildenafil plays a significant role, its role in the degree of drug concentration in the blood increased to enhance. Its role lasted about four hours.

Read More:Sildenafil price