The role of nitric oxide (NO) in erectile physiology is well documented. NO activates relaxation of corporal cavernosal smooth muscle tissue resulting in increased blood flow into the penis resulting in an erection. At present, pharmacologic treatments for erectile dysfunction, such as the phosphodiesterase-5 inhibitors, potentiate the erectile response generated by NO. However, a new class of ...

Phosphodiesterase 4 (PDE4) has been established as a promising target in asthma andchronic obstructive pulmonary disease. PDE4B subtype selective inhibitors are known toreduce the dose limiting adverse effect associated with non-selective PDE4B inhibitors. Thismakes the development of PDE4B subtype selective inhibitors a desirable research goal. Toachieve this goal, ligand based pharmacophore m...

PDE5 inhibitors (PDE5i) are widely known as treatment for erectile dysfunction (ED). This favorable action has emerged as a "side effect" from pioneering studies when PDE5i have been originally proposed as treatment for coronary artery disease (CAD). PDE5i showed marginal benefits for CAD treatment; although disappointing for that indication, they improved systemic and pulmonary vasodilation an...

INTRODUCTION Erectile dysfunction (ED) is the persistent inability to achieve or maintain an erection sufficient for satisfactory sexual performance.1 According to data from the Massachusetts Male Aging Study, up to 52% of men between the ages of 40 and 70 are affected by ED.2 Based on findings from the 2001–2002 National Health and Nutrition Examination Survey (NHANES), it is estimated that 18...

The Nobel Prize winning discovery of nitric oxide (NO) in 1986 was the starting point for a new innovation in drug discovery. NO acting as a mediator at different physiological systems is believed to be involved in many physiological and pathological conditions through the formation of the second messenger cyclic guanosine monophosphate (cGMP). cGMP-dependent vasodilation effect of NO is import...