The Etiologic Mechanism of Some Forms of Hormonally Induced Obesity

Abstract

Hyperadrenocorticism causes obesity and enlargement of the islets of the pancreas due to hypertrophy and hyperplasia of the beta cells, suggesting accelerated release of insulin. It seems unlikely that an excess of circulating corticosteroids can produce obesity directly, since administration of corticosteroids which induces adiposity in control animals, fails to do so in mildly alloxan diabetic animals. Considerable reduction of the food intake does not prevent the increased fat deposition and islet hypertrophy in hyperadrenocorticism. Some strains of mice develop adiposity spontaneously and simultaneously show subcapsular adrenocortical hypertrophy and enlargement of the islets. All these changes can be prevented by adrenalectomy. Adrenalectomy, however, does not affect development of hypothalamic obesity. The obesity seen after castration in animals of suitable species and strains is also associated with hypertrophy of the adrenal cortex and the islets of the pancreas. It is thought that reduction or cessation of the activity of the gonads induces changes in the secretion of the adrenal cortex. This in turn stimulates increased secretion of insulin which produces adiposity.