Effect of DL-homocysteine on some hepatic folate enzymes and folate concentration in cobalamin-deficient rats.
Male weanling wistar rats were fed either a vitamin B12-deficient diet or a vitamin B12-deficient diet supplemented with DL-homocysteine for 12 weeks. The control group was given a vitamin B12-supplemented diet for 12 weeks. Hepatic folate, hepatic, 5,10-methylene THF reductase (EC 1.1.1.68) and hepatic 5-methyl THF; homocysteine methyl transferase (EC 2.1.1.13) activities were assayed in all the rats after killing. The hepatic folate activity was very low among the homocysteine-supplemented rats. 5,10-methylene THF reductase and 5-methyl THF; homocysteine methyl transferase activities were increased in the homocysteine-fed rats. These results show that dietary DL-homocysteine has some regulatory effect on the two enzymes involved in the production of 'free' THF.
D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase / Q000378:metabolism*; D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D000818:Animals; D004032:Diet; D005492:Folic Acid / Q000378:metabolism*; D006710:Homocysteine / Q000494:pharmacology*; D008099:Liver / Q000378:metabolism*; D008297:Male; D008780:Methyltransferases / Q000378:metabolism*; D051381:Rats; D013763:Tetrahydrofolates; D014806:Vitamin B 12 Deficiency / Q000378:metabolism*
D013763:Tetrahydrofolates; D006710:Homocysteine; D005492:Folic Acid; D000429:Alcohol Oxidoreductases; D008780:Methyltransferases; D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase