THE NECESSITY OF DIETARY VITAMIN-B6 TO SELENIUM BIOPOTENCY FOR TISSUE SELENIUM AND GLUTATHIONE-PEROXIDASE IN RATS

Necessity of dietary vitamin B-6 to the biopotency of selenium (Se) for the levels of Se and glutathione peroxidase (GSH-Px) in tissues was investigated. Male Wistar 12-week-old rats were fed a vitamin B-6-Se-deficient basal diet for 3 week, and then the rats were divided into 6 groups. One group was fed the basal diet, the others were fed the diet supplemented with 250-mu-g vitamin B-6/100 g as pyridoxine . HCl, or 0.25 mg Se/kg as Na2SeO3 (SeL) or DL-selenomethionine (Se-Met), or both (SeL + B-6 or Se-Met + B-6) for 10 week. The levels of Se and GSH-Px in erythrocytes and muscle were significantly higher in vitamin B-6-supplemented groups than in vitamin B-6-deficient groups. There was little effect of this vitamin deficiency on Se level in liver of rats fed SeL; however, a higher Se level in liver was observed in vitamin B-6-deficient rats fed Se-Met than in the corresponding B-6-supplemented rats. A significant decrease of GSH-Px activity in liver was found in vitamin B-6-deficient animals fed Se-Met compared with vitamin B-6-supplemented animals, whereas no significant decrease was observed in those fed SeL. These results suggest that this vitamin is involved in the transport and deliverance of Se in plasma to the other tissues and the incorporation of Se from Se-Met to GSH-Px in liver.