SOME EFFECTS OF ANTERIOR PITUITARY EXTRACTS ON NITROGEN METABOLISM, WATER BALANCE, AND ENERGY METABOLISM

Abstract

1. Solutions of the globulin fraction of alkaline extracts of the anterior lobe of beef pituitary glands, when administered intraperitoneally or subcutaneously to dogs for 1 or 2 days, greatly increase the nitrogen balance. Urine nitrogen falls markedly, and at the same time blood non-protein nitrogen decreases, while the nitrogen of the feces remains the same. 2. The nitrogen gained may either be retained or lost again, indicating that it may be converted into reserve protein rather than into permanent structures. Sudden gains in weight which follow the injections are always lost again. 3. The effect of the extracts on protein catabolism is greatest when this is high, as in adult dogs having a negligible positive nitrogen balance, or a negative balance, while consuming a high protein diet adequate in calories. 4. Both the fall in nitrogen excretion, and the subsequent rise, when the latter occurs, are due to changes in urea excretion. 5. Other results of the brief treatments are: great increases in water intake and urine volume, marked thirst, slight rise in temperature, and a remarkable increase in heat production effected by oxidation of fat. Mature female dogs were used, and in one of these lactation occurred after some of the injections.