Some Effects of Depletion and Repletion in Proteins on Body Fluids in Adult Dogs.∗

The plasma albumin decreases markedly while the total plasma globulins decrease slightly below control values in the protein-depleted animal. The dogs are very susceptible to disease in the depleted state, a susceptibility which is reduced upon repletion in proteins. The plasma volume drops and the available fluids increase as the total circulating plasma albumin is reduced by the process of depletion. This nutritional edema is corrected rapidly by repletion in plasma albumin.The excretion of urine nitrogen gradually increases during the feeding of protein nitrogen in the repletion period. This gradual increase is the result of a decrease in the utilization of the protein and of an increase in the excretion of nitrogen from body stores. The decrease in urine nitrogen excretion below normal which occurs in the hypoproteinemic dog is primarily the result of a decrease in ammonia and urea nitrogen.