Cavernous Vessels Smooth Muscle Layer Thickness Correlates with Myocardium Collagen Deposition in High-Fat Fed Rats

Abstract

Vascular aging is associated with progressive deterioration of vascular homeostasis, a phenomenon that affects organs in different extent. The small vessels of the corpus cavernosum (CC) are very sensitive to functional and structural changes, and particularly susceptible to age-related modifications and atherosclerotic occlusion. Penile erection is a vascular event largely regulated by the relaxation of arterial and corporal smooth muscle (SM) that directly relates to its content and integrity, and inversely to that of connective tissue (CT). Corpora expansion also depends on nitric oxide (NO) bioavailability, a molecule with recognized vasodilatory and antifibrotic properties. Thus, endothelial dysfunction mainly provoked by NO loss is currently considered equivalent to vasculogenic erectile dysfunction (ED), and the earliest clinical manifestation of atherosclerosis and systemic vascular disease. Collagen deposition in tissues, such as CC and heart, strongly compromises their function and is one of the causes of ED and cardiac failure, respectively, but as far as we know no correlation between peripheral and cardiac endothelial dysfunction has been already demonstrated. Therefore, we aimed to evaluate morphological structure and collagen deposition in rat CC, myocardium and tail artery during aging, under high-fat diet (HFD) consumption (a strong contributor to endothelial dysfunction onset), and energy restriction.