Studies of the Nature of Antigonadotropic Substances

The fact that long continued injections of certain hormone preparations result in a loss of reactivity in the experimental animal and in the formation, in the serum of an animal so treated, of substances capable of neutralizing the effects of the hormone, has been emphasized and elaborated in the last few years by Collip and his co-workers (1, 2, 3, 4). Korenchevsky (5), in 1930 using an alkaline extract of ox pituitary glands, injecting 1 to 2 cc. daily for 6 to 11 weeks found no increase in body weight, a decrease in the weights of the penis, testes, prostate, and seminal vesicles, and a 17 per cent decrease in the average weight of the thyroid. Siebert and Smith (6) noted that daily subcutaneous injections of either acid or alkaline extracts of the anterior pituitary glands of cattle caused a very marked and rapid rise in the basal metabolic rate of guinea pigs to +60 per cent in 10 days. The rate then fell to +15 per cent when the experiment was continued for 30 days. No such fall was noted on feeding Armour’s desiccated anterior pituitary preparation to another group of rats for 30 days but rather a slow steady rise again to +60 per cent.