[Alterations of the aortic endothelium ultrastructure after the administration of cholesterol oxidation products to rabbits]

Abstract

Intravenous administration of 7 alpha-hydroxycholesterol and cholestane-triol at the dose of 2.5 mg/kg produces, one day later, ultrastructural alteration of aortic endothelial cells such as cytoplasmic vacuolation, protruding and crateriform surface defects, subendothelial oedema with a subsequent exfoliation of endotheliocytes. The endothelial damage was more pronounced after the administration of equal doses of cholestane-triol as compared to 7 alpha-hydroxycholesterol. Ultrastructural changes 10 days after oral administration of 500 mg/kg cholesterol mixed with its auto-oxidation products were similar to those developing after cholestane-triol and 7 alpha-hydroxycholesterol. Cholesterol free of the oxidation products at the same doses did not produce alterations in the rabbit aortic endothelium.