Endothelial Function and Erectile Dysfunction

The vascular endothelium has an important role in modulating vascular tone and blood flow into the penis in response to humoral, neural and mechanical stimuli. Endothelial dysfunction occurs in a variety of pathological conditions in internal medicine, but drugs that improve endothelial function – antihypertensives, statins, antioxidants, etc. – are unable to improve erectile function since they lack specificity of action at the level of the penile vasculature and smooth-muscle cells. Phosphodiesterase type-5 inhibitors (PDE5-i) are a class of drugs that have revolutionised the treatment of male erectile dysfunction. A great debate regarding once-daily administration of PDE5-i for endothelial rehabilitation exists, as it has been demonstrated that these drugs do not produce sustained clinical benefits in terms of erection above those observed with on-demand administration beyond cessation of treatment. The aim of this article is to provide evidence-based data regarding the effect of PDE5- i administration on endothelial function in patients in whom endothelial dysfunction is present.