Relation of glutamate to ammonia production in the rat kidney.

GOLDSTEIN, LEON. Relation of glutamate to ammonia producfion in the rat kidney. Am. J. Physidl. 210(3): 661-666. Ig66.-Glutamate was an effective inhibitor of isolated rat renal glutaminase at concentrations normally found in the kidney. Injection of monosodium glutamate into acidotic rats inhibited renal ammonia excretion about 507~ with no significant effect on urinary PH. Alterations in acid-base balance known to increase (metabolic acidosis) and decrease (metabolic alkalosis) renal ammonia production caused significant changes in renal glutamate concentrations. Metabolic acidosis (40 mmoles NH&l/kg per day) produced a rapid (I day) and sustained (3 days) decrease (35 TO) in glutamate concentrations. Injection of acetazolamide (300 mg/kg per day) reduced glutamate concentration 20% within 3 days. Metabolic alkalosis (40 mmoles NaHC03/kg per day) produced a gradual increase (25%) in glutamate concentration over a period of 3 days. These results suggest that glutamate may play a role in the regulation of renal ammonia production.