Cerebral Effects of Acute Ammonia Intoxication II. The Effect upon Energy Metabolism

Abstract

The effect of ammonia on the regional energy metabolism of the brain was studied in anesthetized rats injected with ammonium acetate. Ammonia intoxication was accompanied by moderate decreases in phosphocreatine content in all regions, possibly caused by a pH-dependent shift in the creatine phosphokinase equilibrium, while the ATP contents were unaltered, αketoglutarate contents were unchanged or even increased. The results did not indicate that ammonia per se causes any change in the energy balance of the tissue, but there was a pronounced increase in the cytoplasmatic NADH/NAD⁺ ratio.

Key Words:

• Ammonia
• labile phosphate
• α-ketoglutarate
• redox state