Is Inhibition of Phosphodiesterase Type-5 by Sildenafil a Promising Therapy for Volume Overload Heart Failure?
Phosphodiesterase type 5 (PDE5) is an enzyme that belongs to a large family of cyclic nucleotide PDEs that catalyze cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). cAMP and cGMP are two essential intracellular second messengers regulating many different cellular functions of living cells. PDE5 specifically breaks down the substrate cGMP. Inhibition of PDE5 increases intracellular cGMP levels by inhibiting its degradation. Sildenafil (Viagra) is a potent and selective inhibitor of cGMP-specific PDE5, and is the first oral treatment for males with erectile dysfunction, which was approved by Food and Drug Administration on March 27, 1998. Sildenafil binds to the catalytic site of PDE5 and inhibits the degradation of intracellular cGMP in smooth muscle within the corpus cavernosum, resulting in increased levels of cGMP that causes smooth muscle cell relaxation, vasodilation, and improves erectile function1,2. (SELECT FULL TEXT TO CONTINUE)
- acute myocardial infarction
- heart attack (myocardial infarction)
- heart failure
- phosphodiesterase inhibitors heart failure
- volume overload
- Received February 6, 2012.
- Accepted February 7, 2012.
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