维生素B6对硒的生物利用率影响的研究Ⅳ．对大鼠体内不同化学形式硒利用率及脂质过氧化物的影响

Effect of dietary vitamin B 6 on selenium bioavailability Ⅳ. Effect of dietary vitamin B 6 on selenium bioavailability from different chemical forms and lipid peroxidation in rats

４周龄雄性大鼠饲缺维生素Ｂ６（ＶＢ６）缺硒酪蛋白蔗糖基础饲料，３周后按体重把动物分成１０组，即基础饲料组、基础饲料中补充含硒０．２５ｍｇ／ｋｇ饲料的硒酸钠组、亚硒酸钠组、ＤＬ－硒蛋氨酸组或硒胱氨酸组，在此基础上每种饲料又分成补充或不补充盐酸吡哆醇２．５０μｇ／ｇ饲料两组。实验期为４周。补ＶＢ６各组的红细胞、骨骼肌和心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对饲硒酸钠、亚硒酸钠和硒胱氨酸大鼠肝硒和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活性显著降低。本研究结果进一步证明，ＶＢ６与血浆硒的转运和利用有关。

Male Wistar rats, 4 week old, fed with vitamin B 6 selenium deficient basal diet( VB 6 Se) for 3 weeks were divided into 10 groups. There were five experimental diets, the basal diet( Se), the basal diet supplemented with Se 0.25mg/kg as Na 2SeO 4,Na 2SeO 3, DL selenomethionine or selenocystine. Each diet was supplemented with or without vitamin B 6 2.50μg/g(250μg/100g) as pyridoxine·HCl (+VB 6) for 4 weeks. The Se concentrations and glutathione peroxidase (GSH Px) activities in erythrocytes, muscle, and heart were significantly higher in vitamin B 6 supplemented (+VB 6) groups than in corresponding vitamin B 6 deficient (-VB 6) groups. VB 6 deficiency had no effect on Se levels in the livers of rats fed with Na 2SeO 4, Na 2SeO 3 and selenocystine, however, Se content was higher and GSH Px activity was lower in VB 6+selenomethionine rats than in the +VB 6+selenomethionine rats. Compared with VB 6 deficiency, the total lipid peroxidation contents in tissues were significantly decreased by VB 6 supplementation which was not related to the chemical forms of Se supplementation. The present results further indicated that dietary VB 6 is related to the transport and utilization of Se, and involved in the metabolic process of liver selenomethionine.