Urinary Output of Nitrogen as Influenced by Intravenous Injection of a Mixture of Amino-Acids

Abstract

Summary

Adult dogs, fed only with sucrose, were immediately brought into N-equilibrium upon intravenous injection of a complete mixture of amino-acids combined with glucose. This appears to demonstrate a high degree of nitrogen retention particularly since nitrogen balance was attained with the administration of an amount of nitrogen but slightly in excess of the previous level of excretion. This was impossible if the mixture did not contain added tryptophane and cystine; under such conditions a large part of the injected nitrogen appeared in the urine. These observations would Seem to indicate that the mixture of amino-acids used, as prepared by the acid hydrolysis of casein plus 2% tryptophane and added cystine, is efficiently utilized by the body, probably in the active synthesis of body protein.