Is alcohol hepatotoxic in the baboon?

The baboon is the only animal in which alcoholic fibrosis and cirrhosis of the liver has been produced with a nutritionally adequate diet. Zinc deficiency is associated with alcoholic liver disease and may contribute to liver damage. We have therefore investigated whether zinc supplementation would reduce liver damage in ten baboons receiving ethanol and an adequate diet. Eight received ethanol at up to 25 g/kg/day (70% of calories) for up to 60 months (four were supplemented with 50 mg zinc/day). All animals gained weight, and blood concentrations of ethanol were 63-342 mg/dl. Changes in liver blood tests were slight. Liver histology only showed fatty change in six animals, severe in two, and minor inflammatory changes but no significant fibrosis or cirrhosis. In one of the animals with severe fatty change there were also degenerative changes in parenchymal cells. There was thus no significant hepatic fibrosis or cirrhosis in baboons given large amounts of ethanol and an adequate diet for up to 5 years.