Vitamin B-6 metabolism and turnover in the ethanol-fed rat.
The effect of long-term ethanol supplementation on vitamin B-6 metabolism and storage was studied in McCollum rats receiving approximately 30% of their caloric intake as ethanol. Hepatic pyridoxal 5'-phosphate levels were significantly depressed in the ethanol-fed animals. However, total hepatic vitamin B-6 levels were slightly higher than in control animals because of a marked increase in pyridoxamine 5'-phosphate levels. The metabolism of a labeled pyridoxine dose appeared unaffected by ethanol administration, with the final distribution of labeled metabolites, almost entirely pyridoxal 5'-phosphate and pyridoxamine 5'-phosphate, mirroring that observed with unlabeled endogenous vitamin B-6. The daily turnover of total-body vitamin B-6 stores in ethanol-fed animals (2.7%) was lower than in control animals (3.8%). Whether this resulted from ethanol administration or a reduced vitamin B-6 intake was not ascertained. However, it was apparent that ethanol did not increase the turnover of total-body vitamin B-6 or decrease total-body stores of the vitamin, which were similar in both groups of animals on a body store per kilogram weight basis. Pyridoxic acid excretion reflected vitamin B-6 intake in both groups of animals and accounted for approximately 30% of the total excreted vitamin.
D000437:Alcoholism / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D001921:Brain / Q000378:metabolism; D005260:Female; D006801:Humans; D008099:Liver / Q000378:metabolism*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D009943:Organophosphorus Compounds / Q000378:metabolism; D011247:Pregnancy; D011730:Pyridoxal / Q000378:metabolism; D011732:Pyridoxal Phosphate / Q000378:metabolism; D011733:Pyridoxamine / Q000031:analogs & derivatives / Q000378:metabolism; D011735:Pyridoxic Acid / Q000652:urine; D011736:Pyridoxine / Q000378:metabolism*; D051381:Rats
D009943:Organophosphorus Compounds; D011730:Pyridoxal; D011735:Pyridoxic Acid; D011732:Pyridoxal Phosphate; D011733:Pyridoxamine; D011736:Pyridoxine; C010627:pyridoxamine phosphate