Adrenocortical dysfunction induced by cholesterol feeding in New Zealand white rabbits: Correlated morphometric and biochemical study.

摘要

The hypercholesterolemic and atherogenic effects of high cholesterol diet and inhibition of fatty streak formation by glucocorticoid therapy in the rabbit are well known. Despite these observations, few studies have examined the effects of cholesterol feeding on adrenocortical structure and function. In this study, effects of a 1% cholesterol diet given to male NZW rabbits for 4 and 14 days on plasma levels of cholesterol, cortisol, and ACTH were determined and compared to those of controls fed standard chow. Plasma cortisol levels were strongly depressed in cholesterol-fed animals (p ;A light and electron microscopic morphometric study of the zona fasciculata within the adrenal cortex was also performed. This analysis revealed that (1) volume fractions (V;To establish whether the endocrine dysfunction was localized to the adrenal cortex rather than the anterior pituitary, two rabbits were challenged with rat corticotropin releasing factor (rCRF) before and at 4 and 14 days of cholesterol feeding. Cortisol, but not ACTH, production was suppressed upon rCRF challenge at 4 and 14 days of cholesterol feeding, while the former was normal prior to CF.;It is proposed this deficit in plasma cortisol levels reflects pathophysiologic changes in the adrenal cortex resulting from ischemia. This pronounced decline in cortisol output may trigger the arterial inflammatory response characteristic of atherosclerosis in cholesterol-fed New Zealand white rabbits.