Some effects of excess methionine on lipide metabolism in the rat

Abstract

Wistar rats fed a synthetic diet containing 4.8% excess dl-methionine for 28 days showed increased serum and carcass cholesterol, and decreased total carcass lipide compared to pair-fed controls. The incorporation of acetate-2-C 14 into hepatic cholesterol in vivo and in vitro was significantly greater in the methionine-fed animals, but incorporation of acetate-2-C 14 into fatty acids of adipose tissue was much less than in controls. In methionine-fed animals, liver fatty acid was unchanged, and liver cholesterol increased in comparison to the levels observed in pair-fed controls. Methionine-fed and control rats produced respiratory C 14O 2 from injected labeled acetate at approximately the same rate; however, liver slices from animals fed excess amino acid showed a depression in the production of C 14O 2 from acetate-2-C 14 when compared to control slices. The results were discussed with reference to some similarities to the derangements in fat metabolism in the diabetic rat.