Down‐regulation of endothelin‐B receptor sites in cavernosal tissue of hypercholesterolaemic rabbits

Abstract

Objective To investigate the density and distribution ofResults ET-1, ET A and ET B receptor binding sites were primarily localized to the smooth muscle cells of the endothelin-1 (ET-1) and endothelin receptor subtypes in cavernosal tissue of healthy New Zealand White corpus cavernosum and the endothelium lining the cavernosal spaces. There was a significant decrease in (NZW) rabbits (controls) and to assess any changes in a genetic model of hypercholesterolaemia (the ET B receptor binding sites in cavernosal tissue from HC rabbits when compared to age-matched healthy Watanabe rabbit). Materials and methods Penises were excised from six controls. Conclusions The findings suggest that ET-1 may have a hypercholesterolaemic (HC) rabbits 6 months after birth. Low-and high-resolution autoradiography was perrole in the pathophysiology of erectile dysfunction in HC. These eCects may partly be due to enhanced formed on cavernosal sections using radioligands for ET-1, endothelin A (ET A ) and endothelin B (ET B ) recepvasoconstrictor actions and smooth muscle cell proliferation, consequent on a reduction in endothelial tors, and the autoradiographs analysed densitometrically. The results were compared with those from ET B receptors. Keywords Endothelin-1, endothelin B receptor, corpus six age-matched control rabbits. Immunohistochemical localization of ET-1-like immunoreactivity was cavernosum, hypercholesterolaemia, erectile dysfunction also performed on adjacent cavernosal sections. preferentially released from vascular endothelium.

Endothelial function in patients with vasculogenic erectile dysfunction

“…Hypercholesterolemia is another recognized risk factor for both vasculogenic ED and atherosclerosis. Studies using a genetic rabbit model of hypercholesterolemia suggest that this lipid abnormality may account for ED because of the changes in penile endotheline receptor distribution [31]. Increasing age correlates with altered NO synthesis and erectile responses in the rat penis [32], which might be an explanation for the increasing incidence of ED with aging in humans.…”

Increased contractility of diabetic rabbit corpora smooth muscle in response to endothelin is mediated via Rho-kinase β

“…20 In a separate study, they reported a decrease in ETB receptor binding sites in the cavernosal tissue of hypercholesterolemic rabbits. 21 However, none of these studies examined whether there were any changes in the physiological response of the CCSM to ET-1 or in the downstream regulators of ET-1-induced contraction.…”

The promise of inhibition of smooth muscle tone as a treatment for erectile dysfunction: where are we now?

“…Chang et al 4 found that the expression of ET A receptors was significantly upregulated in the CSM of diabetic rabbits. Sullivan et al 25 reported a significant decrease in ET B receptor binding sites in cavernosal tissue from hypercholesterolemic rabbits, and a significant increase in ET B receptor binding sites in cavernous tissue of diabetic rabbits. 26 5-HT.…”