Renal ammoniagenesis and tissue glutamine, glutamine synthetase, and glutaminase I levels in potassium-deficient rats.

Abstract

Abstract Rats rendered potassium-deficient by dietary deprivation exhibit increased urinary ammonia excretion, increased renal venous blood ammonia levels, and systemic hyperammonemia. Renal ammoniagenesis in potassium-deficient rats is associated with increased renal glutaminase I activity, but unchanged renal glutamine concentration and glutamine synthetase activity. Muscle glutamine, glutaminase I, and glutamine synthetase levels are unchanged in potassium deficiency. Hepatic glutamine concentration and glutamine synthetase activity increases greatly in potassium-deficient rats. This glutamine probably becomes available to the kidney for ammoniagenesis as part of the metabolic adaption to potassium deprivation in the rat.