EFFECT OF AMINO-ACIDS ON THE EXCRETIONS OF PURINE-BASES AND OXYPURINOL

To investigate whether or not amino acids affect the urinary excretion of purine bases and oxypurinol, a 12% amino acid solution was infused to 6 subjects who took allopurinol (300 mg) 6 h before the study. Ami no acid infusion increased the urinary excretion and the fractional cl earance of uric acid and oxypurinol and decreased the plasma concentra tion of oxypurinol. However, it affected neither the urinary excretion , the fractional clearance, the plasma concentration of oxypurines nor the plasma concentration of uric acid. These results indicate that am ino acids affect the renal transport pathways of oxypurinol and uric a cid but not those of oxypurines. In addition, it was suggested that th e amino acid-induced increase in the urinary excretion of oxypurinol m ay be considered when allopurinol is administered to hyperuricemic pat ients with hypoproteinemia who have taken amino acids either orally or intravenously.