Ammonia toxicity and relative
sodium benzoate toxicity alters the energy metabolism, leading to a decrease of
adenosine triphosphate and free
coenzyme A levels. The object of the present study was to analyze the hepatic and muscular
acyl-coenzyme A profiles in chronically hyperammonemic mice treated with varying doses of the
sodium benzoate. An enzymatic method was used for the measurement of free
coenzyme A, acetyl-
coenzyme A, and medium and long chain
acyl-coenzyme A. Untreated chronic
hyperammonemia resulted in a decrease in
acetyl-coenzyme A and an increase in the long chain
acyl-coenzyme A in the liver, accompanied by an increase in total
coenzyme A in the muscular tissues. Treatment with
sodium benzoate at moderate doses, caused a decrease in the hepatic free and esterified
coenzyme A while these were increased at higher doses. We conclude that chronic
hyperammonemia is responsible for qualitative changes in the free and esterified
coenzyme A profile in the liver, while causing qualitative and quantitative changes in the muscular tissue, probably due to an inhibition of mitochondrial oxidation. The
sodium benzoate had a biphasic effect on the hepatic content of free and esterified
coenzyme A, suggesting a degradation of
coenzyme A at moderate doses. However, at a higher dose of
benzoate, the possibility of
glycine mobilization and/or a significant formation of acylcarnitines is proposed as an important factor in an increase of the hepatic total
coenzyme A.