Effect of L-carnitine on ethanol metabolizing enzymes

The effects of L-carnitine on ethanol metabolism were examined. On the seventh day of oral administration of a 3g/Kg body weight/day dose of ethanol there were 2-3 fold increases in the blood ethanol concentrations of L-carnitine supplemented rats. The in vitro addition of L-carnitine to purified equine liver alcohol dehydrogenase did not significantly alter enzymatic activity or Km and Vmax values. The in vitro addition of L-carnitine to subcellular fractions of rat liver did not significantly affect alcohol dehydrogenase, microsomal ethanol oxidizing system or catalase activities. 0.5% dietary carnitine supplementation was without significant effect on alcohol dehydrogenase and microsomal ethanol oxidizing system kinetics. Carnitine supplementation also did not affect the activity of aldehyde dehydrogenase or catalase. Microsomal ethanol oxidizing systems activity was increased following the oral administration (Ig or 3g/kg body weight/day) of ethanol for seven days. However, the increases were not significant and not affected by carnitine. Dietary carnitine supplementation results in elevated blood-ethanol concentrations without affecting the kinetics or intrinsic levels of the enzymes responsible for ethanol oxidation.