Developmental aspects of steroid-induced ammonia release from isolated sections of rat intestine.

Release of ammonia from isolated intestinal sections of adult male rats is higher than that measured using immature animals. The increase appears to be Na+ dependent and develops during the spurt of growth at puberty. Developmental changes in Na+-dependent ammonia release from isolated sections of the intestine and growth of the small intestine in male and female rats have been compared. Intestinal growth increases far more rapidly than body weight and in the males critical developmental changes occur early during weaning and during puberty. In females the major change is at weaning and little further change occurs during puberty. Treatment of young animals with aldosterone or testosterone increases the Na+-dependent ammonia release precociously. Dose-response effects of testosterone and aldosterone in distal sections of the small intestine have been compared.