Suppression of Adrenal Compensatory Hypertrophy by Hypothalamic Lesions.

Abstract

Unilateral adrenalectomy in normal male rats resulted within 14 days in hypertrophy of the remaining right adrenal of 51-8%, when the weight of this gland was compared with the previously removed left adrenal. Hypothalamic lesions which interrupted a significant fraction of the supraoptico-hypophyseal tract as evidenced by diabetes insipidus suppressed this effect. The degree of suppression was inversely related to severity of the diabetes insipidus and maximum suppression occurred in animals with a water intake of greater than 100 ml/day. However, such animals still gave a residual hypertrophy which was 30% of that of the control rats. Lesions interrupting the supraoptico-hypophyseal tract could at least partially block the augmented release of ACTH which normally follows unilateral adrenalectomy.