Kidney metabolite levels and ammonia production in acute acid-base alterations in the rat.
Acute acid-base disturbances cause rapid changes in renal ammonia production in the rat. To investigate the regulation of ammonia production in acute acid-base stresses, we examined the effects of such conditions on tissue levels of metabolites such as alpha-ketoglutarate (KG), which inhibits kidney mitochondrial glutamine uptake and deamidation at physiological concentrations. In rats given low (5 mmol/kg) or high (20 mmol/kg) doses of NH4Cl by stomach tube or placed in a 10% CO2 atmosphere, kidney KG levels fell after 1-h by 44, 69, or 73%, respectively. NaHCO3  administration produced no change in KG levels. Renal glutamate and glutamine levels changed little, if at all, in any group, and renal phosphoenolpyruvate levels were not altered except for a decrease in the NH4HCO3 group. In livers of the same rats, treatments produced different patterns of metabolite changes; KG fell only in the NaHCO3 and NH4HCO3 groups. These results support the concept that KG is a specific regulator of renal ammonia production in acute acid-base stresses.
D000137:Acid-Base Imbalance / Q000378:metabolism*; D000641:Ammonia / Q000378:metabolism*; D000818:Animals; D005973:Glutamine / Q000378:metabolism; D005977:Glutarates / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D007773:Lactates / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008293:Malates / Q000378:metabolism; D008297:Male; D010728:Phosphoenolpyruvate / Q000378:metabolism; D051381:Rats
D005977:Glutarates; D007773:Lactates; D008293:Malates; D005973:Glutamine; D010728:Phosphoenolpyruvate; D000641:Ammonia