Abstract
SUMMARY: 1. Male and female rats of 3½ months of age gained weight when treated with methylandrostenediol (MAD). The nature and extent of the response varied with the age of the animal. 2. Chemical analysis of the whole rat showed a gain of protein and water and a loss of fat as a result of MAD treatment. Such changes can be taken as indicative of tissue growth. 3. The water/protein ratio of the new tissue is similar to that of muscle. 4. Since similar results were obtained with hypophysectomized and with adrenalectomized rats, the anabolic action of MAD does not depend upon the presence of adrenal or pituitary hormones.