THE RENAL TUBULAR RESPONSE TO AMINO ACID LOADING 1

Abstract

In previous studies from this laboratory (1) it was shown that renal tubular reabsorption of filtered amino acids was virtually complete in the fasting state. However, when a solution of amino acids was administered intravenously and the load filtered by the kidney thus increased, both the amounts of amino acids reabsorbed and those ex- creted were increased. In quantitative terms the more noteworthy event was the increase in amount reabsorbed. Considerable selectivity was exhibited in the reabsorption of individual amino acids and evidence was obtained which was interpreted as indicating a "competition" for reabsorption between cystine and one or more other amino acids.