Effects of a Single Large Dose of Ethanol on Tissue Ascorbic Acid, Drug-Metabolizing Enzymes in the Liver, and Serum and Liver Lipids in Rats Fed with a PCB-containing Diet.

Abstract

The effects of a single administration of ethanol after feeding a PCB-containing diet on tissue ascorbic acid, drug-metabolizing enzymes in the liver, and serum and liver lipids of rats were investigated. Male Donryu and Wistar rats that had been fed on a 20% casein diet with or without 0.03% PCB were given a 5g/kg of body weight ethanol solution (25%, w/v) via a stomach tube, and then killed 16h after the intubation. Intake of the PCB-containing diet accelerated the disappearance of blood ethanol. Dietary PCB and a single dose of ethanol independently affected the tissue levels of ascorbic acid. The combined effect on hepatic aniline hydroxylase activity was additive or synergistic. A single dose of ethanol did not significantly affect the hepatic aminopyrine N-demethylase activity. In Donryu rats, the effects from feeding on a PCB-containing diet and those from a single dose of ethanol on serum lipids were almost additive. In Wistar rats, the effects of ethanol alone on lipids were not necessarily apparent, but the effects of ethanol after feeding with the PCB-containing diet were strongly enhanced. Ethanol alone hardly affected the liver lipids. Most lipids that were increased by PCB alone were significantly decreased or tended to be decreased by a single dose of ethanol. The serum levels of GOT and GPT were markedly increased by a single large dose of ethanol concomitant with the PCB-containing diet in both strains of rats; however, PCB alone or ethanol alone hardly changed the serum levels of GOT and GPT. These results indicate that the effects of a single large dose of ethanol on drug and lipid metabolism, and on the liver function were markedly modified by the intake of a PCB-containing diet.