Erectile Dysfunction Due to Atherosclerotic Vascular Disease: The Development of an Animal Model

Abstract

An animal model was developed to study the pathophysiology of erectile dysfunction due to atherosclerotic vascular disease. Thirty one New Zealand white male rabbits were divided into control (n = 5) and treatment groups (n = 26). The control group was placed on a regular diet while the treatment group underwent balloon de-endothelialization of the aorto-iliac arteries and received 1.6% cholesterol and 4% triglyceride diet for eight weeks. After eight weeks in the control animals (n = 5), blood levels of cholesterol, triglycerides and low density lipoproteins, radiologic studies as well as hemodynamic parameters of erectile function were all normal. In the surviving treatment animals (n = 21) after the same time period, a significant increase in blood levels of cholesterol, triglyceride and low density lipoprotein were observed. In addition, 62% of these animals developed hypertension which was not observed in the control group. Angiographically, 10 animals (48%) demonstrated severe atherosclerotic lesions (75% to 100% occlusion of common or internal iliac arteries on one side and over 50% occlusion of the opposite side), five (24%) had moderate lesions (50 to 75% luminal occlusion of right and left common iliac or internal iliac arteries) and 6 revealed minimal lesions (less than 50% occlusion of the right and left common iliac or internal iliac arteries). Of the 15 animals with 50% or greater luminal occlusion of the iliohypogastric arteries, erectile dysfunction was found in 93% of cases. Due to the development of erectile dysfunction in 33% of animals with minimal occlusive lesions, it appears that factors, other than large vessel luminal occlusion, may exist in this animal model which adversely influence erectile function. This model may therefore be of further benefit in the study of other factors associated with atherosclerosis and impotence, such as the possible concomitant hypercholesterolemic and atherosclerotic-induced alterations in the local reactivity of corpus cavernosum smooth muscle and lacunar space endothelial cells.