Influence of ethanol on in-vivo levels of hepatic methylators betaine and N⁵ methyltetrahydrofolate in the rat

Rats were fed an alcohol-containing diet for periods of 30 days and 60 days. The feeding of this diet produced an accumulation of N⁵-methyltetrahydrofolate and a decrease in the pool size of betaine in livers at both time periods. Hepatic choline was elevated as a result of the ethanol but phosphorylcholine and the activities of choline kinase and choline oxidase did not change. These findings suggest that betaine may substitute for N⁵-methyltetrahydrofolate as a methylator of homocysteine in methionine synthesis when methylation by N⁵-methyltetrahydrofolate is impaired by ethanol.