Adrenocortical function in arteriosclerotic female breeder rats

The in vitro production of a-ketolic adrenal steroids was compared in female breeder and virgin rats. The breeders were divided into groups showing gross arteriosclerosis and another group with similar but early or microscopic lesions only. It was found that the adrenal glands of rats with arteriosclerosis show a decreased in vitro responsiveness to ACTH. These studies further indicate that there is abnormal biosynthesis of adrenal steroids in arteriosclerotic animals despite the ready availability of steroid precursor materials such as adrenal cholesterol. Histologically, the adrenal glands of arteriosclerotic female breeder rats show hypertrophy and hyperplasia and in some animals, cortical infarction. Exhaustion of the adrenal cortex is apparent as the arteriosclerosis becomes severe. Since the arterial lesions consist of alterations in connective tissue elements and ground substance, it is postulated that there may be a relationship between the altered adrenal steroidogenic patterns and the connective tissue changes in the arterial wall of these arteriosclerotic breeder rats.