Plasma free amino acids in the chronically uremic rat.

Plasma free amino acids in the sub-totally nephrectomized chronic uremic rat have been quantitated. The concentrations of these substances in uremic rats have been compared to levels present in sham-operated controls, and to levels found in normal rats on a restricted diet. Phosphoserine, alpha-aminoadipic acid, 1-methylhistidine and 3-methylhistidine concentrations were found to be significantly higher in the uremic group. Sub-normal amounts of serine, valine, tryptophan, asparagine and anserine were present in the serum of the uremic animals. No changes were detected in serum amino acids which are ketogenic. Serum glutamic oxaloacetic transaminase activity was reduced in both uremic and restricted diet rats.