膳食维生素B_6对硒的生物利用率影响的研究──Ⅲ．对成年大鼠组织中硒和谷胱甘肽过氧化物酶水平的影响

Effect of dietary vitamin B_6 on selenium bioavailability Ⅲ. Study on the necessity of dietary vitamin B6 to selenium biopotency for tissue selenium and glutathione peroxidase in adult rats

１２周龄雄性大鼠饲缺维生素Ｂ６（ＶＢ６）缺硒酪蛋白蔗糖基础膳食，３周后按体重把动物分成６组。分别喂饲三种膳食，即基础膳食、基础膳食中补充硒０．２５ｍｇ／ｋｇ的亚硒酸钠或ＤＬ－硒蛋氨酸，在此基础上每种膳食又分为补充（２．５μｇ／ｇ）或不补充盐酸吡哆醇两组。实验期为１４周。补Ｖ８６各组的红细胞和骨骼肌中硒水平和谷胱甘肽过氧化物酶（ＧＳＨ－Ｐｘ）活性均显著高于相应缺ＶＢ６各组，ＶＢ６对饲亚硒酸钠大鼠肝硒和ＧＳＨ－Ｐｘ水平没有影响；但当补充硒蛋氨酸时，与补ＶＢ６大鼠相比缺ＶＢ６大鼠的肝硒水平较高而ＧＳＨ－Ｐｘ活性则显著降低。这些研究结果进一步证明，ＶＢ６与血浆硒的转运和硒的利用有关，并且可能参与了硒蛋氨酸在肝脏中的代谢过程。

Male Wistar rats,12-week-old,fed with vitamin B6-Se-deficient basal diet(-VB6-Se)for 3 weeks were divided into 6 groups. There were three experimental diets, the basal diet(-Se), the basal diet supplemented with Se 0.25mg/kg as Na2SeO3(+SeL) or DL-selenomethionine(+SeMet). One group fed with each diet was supplemented with vitamin B6 2. 50μg/g as pyridoxine·HC1(+VB6)for 14 weeks. The levels of Se and GSH-Px in erythrocyte and muscle were significantly higher in vitamin B6 supplemented(+VB6) groups than in vitamin B6-deficient(-VB6)groups. There was a slight effect of VB6 deficiency on Se level in liver of rats fed with SeL.However, a higher Se level in liver was observed in -VB6 +SeMet rats than in the +VB6 +SeMet rats. A significant decrease of GSH -Px activity in liver was found in -VB6+SeMet animals compared with + VB6 + SeM et animals, whereas no significant decrease was observed between the groups fedVB6+SeL and+VB6+SeL diets. These results suggest that VB6 is involved in the transportation and availability of Se in plasma to other tissues and the incorporation of Se from SeMet to GSH-Px in liver.