Acute Effects of Hypercholesterolemic Diet on Erectile Responses in Rats

Abstract

Objective: The aim of this study was to evaluate the acute effects of a high cholesterol diet (HCD) on erectile and endothelial functions in Sprague-Dawley rats. Materials and Methods: Sprague-Dawley rats were divided into 2 groups as control and HCD groups. The control group was fed on a normal diet and the hypercholesterolemia group was fed a 1% cholesterol-enriched diet daily for 2 weeks. Total cholesterol levels were measured at the end of 2 weeks in both groups. To examine the effect of HCD on erectile function, electric cavernous nerve stimulation (CNS) at 20 Hz with a pulse duration of 1 ms for 1 min at 5 V was performed. During CNS, we measured intracavernous pressure (ICP), mean arterial pressure (MAP), detumescence time and area under the curve (AUC). To evaluate the endothelial responses, acetylcholine (Ach) was applied cumulatively (1 nM to 1 µM) to thoracic aorta tissues contracted with 60 mM KCl. Results: In the HCD group total cholesterol levels were significantly higher than in the control group (148.1 ± 18.9 vs. 55.7 ± 8.1 mg/dl, p = 0.002). The detumescence time was significantly decreased after HCD compared to the control diet (19.3 ± 3.6 vs. 78.6 ± 12.8 s, p < 0.001). The decreases in the HCD group were also significant in terms of ICP (53.4 ± 4.5 vs. 35.6 ± 5.5 mm Hg; p < 0.05), ICP/MAP (55.9 ± 3.9 vs. 38.2 ± 5.2%; p < 0.05) and AUC (1,404 ± 197.1 vs. 2,250 ± 253.7, p < 0.05) values. There were no significant changes in maximum relaxation responses of the thoracic aorta to Ach. Conclusion: These results suggest that erectile functions were significantly damaged early in HCD rats. However, endothelial functions, evaluated in the thoracic aorta, were not affected simultaneously with erectile functions in rats fed a low concentration of HCD.

Independent Predictors of Erectile Dysfunction in Type 2 Diabetes Mellitus: Is It True What They Say about Risk Factors?

“…Whereas they revealed diabetes as only factor associated with penile atherosclerosis. In addition some experimental studies exhibited that erectile function were significantly damaged in hyperlipidemic conditions because of some structural change of penile vessels [30, 31]. Our study did not show any relation between impaired lipid profile or hypertension, the known risk factors of atherosclerosis, and ED in patients with T2DM.…”

Mechanistic link between erectile dysfunction and systemic endothelial dysfunction in type 2 diabetic rats

“…Several studies in animal models of vasculogenic ED reported endothelial dysfunction in the penile vascular bed occurring prior to this effect in the aorta, coronary, and mesenteric arteries, supporting our findings. For example, in rats fed high cholesterol or Western diet, erectile function was impaired after 2 and 8 weeks, respectively, while endothelium-dependent relaxation of the thoracic aorta and coronary artery were maintained at these times (Demir et al, 2010; La Favor et al, 2013). In obese Zucker rats, a genetic model of insulin resistance, endothelium-dependent relaxation in the dorsal penile artery was decreased at the time (17–18 week of age) when no endothelial dysfunction was present in the coronary artery (Villalba et al, 2009).…”

Do penile haemodynamics change in the presence of hydrogen sulphide (H2S) donor in metabolic syndrome-induced erectile dysfunction?

“…Erectile function was measured by electrical stimulation of the cavernous nerve which was performed with pulse duration of 1 ms for 1 min at 5 V and 20 Hz. ICP and MAP were measured as described previously (Bal et al., ; Demir et al., ; Figure ).…”