Biochemical and histocytochemical studies on response of ammonia-producing enzymes for nh4cl-induced acidosis.

NH4Cl-induced acidosis in rats resulted in renal enlargement and increase in activities of phosphate-dependent glutaminase and glutamic dehydrogenase. The renal enlargement was associated with protein synthesis but not deoxyribonucleic acid synthesis. In control rats histochemical activity of glutamic dehydrogenase was seen dominantly in the proximal straight tubule. In acidotic rats high activity was noted in the proximal convoluted tubule as well as in the proximal straight tubule. By electron microscopy reaction product was in mitochondria. The results suggest that urine ammonia is produced in mitochondria of epithelial cells in the proximal straight tubule in both normal and acidotic rats. Increased enzyme activity in acidotic rats is largely associated with epithelial cells of the proximal convoluted tubule.