The metabolism of acetate in the perfused hind-quarter of the rat.

Abstract

The elimination kinetics of acetate, the main end product of ethanol metabolism in the liver and the influence of acetate oxidation on the redox- and energy state of the isolated perfused hind-quarter of the rat were studied. The rate of acetate uptake increased with increasing initial concentration of acetate in the perfusion medium, suggesting that the plasma level of free acetate may be one factor in the regulation of acetate uptake in the skeletal muscle. Addition of acetate as a single dose did not affect the net production of lactate or the uptake of glucose. In continuous infusion experiments at a constant concentration of 2 mM of acetate in the medium, the lactate/pyruvate ratio was unaffected in the medium and in the muscle tissue. Addition of acetate did not affect the oxygen uptake. Experiments with 14-C-acetate showed that about 50% of added radioactivity was found in form of 14-CO2 accounting for 25 to 45% of the oxidative metabolism in the muscle tissue. It was calculated that about 25% of the acetate produced in the liver during ethanol oxidation can be consumed in the resting, perfused hind-quarter of the rat. The tissue content of high-energy phosphate compounds was not significantly affected by acetate.