title: Influence of vitamin B6 status on aspects of lead poisoning in rats.
abstract: The effects of vitamin B6 status and lead (Pb) toxicity on aspects of glutathione (GSH) metabolism in rats were examined in a 2 x 2 factorial experiment. The administration of 2000 ppm Pb as Pb acetate.3H2O significantly (P less than 0.05) increased hepatic GSH levels in rats receiving B6-adequate (+B6) but decreased GSH in rats fed B6-deficient (-B6) diets. The addition of Pb to the +B6 diet also increased hepatic glutathione reductase (GSSG-R) activity. Plasma pyridoxal phosphate (PLP), cystathionine and valine levels were decreased by the -B6 diets independent of the presence of Pb. Plasma arginine, alanine, serine and proline levels were increased by Pb in both -B6 and +B6 groups. Glycine levels were increased in -B6 rats only in the absence of Pb while taurine was decreased by Pb only in +B6 rats. There were significant -B6 x Pb interactions for hepatic GSH, cysteine and GSSG-R as well as plasma valine, glycine and proline. These results suggest an influence of B6 status on Pb-induced changes in hepatic GSH, possibly through its role as a co-factor for enzymes involved in amino acid metabolism.
authors.affiliation: Food Science and Human Nutrition Department, University of Florida, Gainesville 32611.
authors.forename: C
authors.initials: C
authors.lastname: McGowan
mesh_terms: D000596:Amino Acids / Q000097:blood*; D000818:Animals; D003067:Coenzymes / Q000008:administration & dosage; D003545:Cysteine / Q000378:metabolism; D004032:Diet; D005978:Glutathione / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D007855:Lead Poisoning / Q000097:blood / Q000378:metabolism*; D008099:Liver / Q000201:enzymology; D008297:Male; D011732:Pyridoxal Phosphate / Q000097:blood; D011736:Pyridoxine / Q000008:administration & dosage; D051381:Rats; D011919:Rats, Inbred Strains; D013223:Statistics as Topic; D026681:Vitamin B 6 Deficiency / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D003067:Coenzymes; D011732:Pyridoxal Phosphate; D005980:Glutathione Reductase; D005978:Glutathione; D003545:Cysteine; D011736:Pyridoxine