Hyperalimentation in Normal Animals Produced by Protamine Insulin

Abstract

Regular insulin in doses of 1 to 5 units per 100 gm. body weight per day had no measurable effect upon the food intake or body weight of albino rats. The slowly absorbed protamine zinc insulin in similar doses had a remarkable influence upon the appetite. The food intake could be more than doubled in this manner leading to large increases in body weight. The chief factor leading to the increased appetite appeared to be the decrease in the blood sugar level, for an inverse relationship between the latter and the food intake was demonstrated in the rabbit. Furthermore removal of the adrenal medullas, thus preventing the secretion of epinephrine when stimulated by hypoglycemia, and the ensuing blood sugarraising effect led to greater weight gains from a given dose of insulin.