Folate metabolism in the ethanol-fed rat.
The effect of long-term ethanol supplementation on folate metabolism was studied in McCollum rats receiving approximately 30% of their caloric intake as ethanol. Ethanol did not significantly affect hepatic or plasma total folate levels. The net hepatic uptake and metabolism of a labeled folate dose to polyglutamate forms were unimpaired by ethanol administration. In fact, the ethanol-fed animals metabolized hepatic pteroylmonoglutamates to polyglutamate forms, predominantly the pentaglutamate, at a slightly faster rate than the control animals, and the net hepatic uptake of the labeled dose was higher than in the controls. Tetrahydrofolate derivatives were the predominant one-carbon form of folate in the livers of ethanol-fed and control animals, although the proportion of folate in the 5-methyltetrahydrofolate form was slightly increased after ethanol supplementation. Although hepatic metabolism of folate appears to be unimpaired in the ethanol-fed rat, an increased rate of pteroylpolyglutamate synthesis, with a resulting increase in the tissue storage of folate, might be a contributing factor to the low serum folate levels reported in alcoholics.
D000437:Alcoholism / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D005260:Female; D005492:Folic Acid / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000033:anatomy & histology / Q000378:metabolism*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D011247:Pregnancy; D011624:Pteroylpolyglutamic Acids / Q000378:metabolism; D051381:Rats; D013763:Tetrahydrofolates / Q000378:metabolism
D011624:Pteroylpolyglutamic Acids; D013763:Tetrahydrofolates; D005492:Folic Acid; C005984:5-methyltetrahydrofolate