THE RENAL REABSORPTION OF AMINO ACIDS IN DOGS: VALINE, LEUCINE AND ISOLEUCINE

Abstract

The renal reabsorption of a-amino N of dl-valine, 1-leucine, and dl-isoleucine in unanesthetized 9 dogs was studied at various plasma concns. obtained by infusion of the individual amino acids. Inulin clearance was used as a measure of glomerular nitration rate. Plasma amino N concs. ranged from 4-30 mg. % and amino N filtration rates from 4-29 mg./min./sq. meter of body surface. With each acid, rate of reabsorption of a-amino N increased progressively as the rate of filtration was raised through certain levels. Gradually, however, a maximal rate of reabsorption was reached. At low levels of nitration, the rates of reabsorption of valine and isoleucine were approx. the same and were lower than that of leucine. At higher levels, the maximal rates of reabsorption of leucine and isoleucine were of about the same magnitude, the avg. value for each lying between 9 and 10 mg./-min./sq. m. of body surface. The maximal limit for valine was somewhat higher, averaging about 13 mg./min./sq. m.