Pazak H E, Scholz R W
Department of Veterinary Science, Pennsylvania State University, University Park 16802, USA.
Int J Vitam Nutr Res. 1996;66(2):126-33.
Long-Evans hooded female rats previously acclimated to one of four experimental diets differing in their vitamin E (E) and selenium (Se) contents were used in these studies. The basal diet (-E -Se) was marginal in E (15 IU/kg) and Se (0.03 mg/kg) content. Three additional diets, -E, +Se, +E-Se and +E +Se were prepared by supplementing the basal diet with dl-alpha-tocopheryl acetate to contain 150 IU/kg or with sodium selenite to contain 0.5 mg/kg, as required. The rats were mated and the pups born were used to provide plasma, heart, lung and liver tissue for E analyses at postpartum intervals from birth (prior to nursing) to 21 days of age. Differences in Se nutrition of the dams during the perinatal period did not affect the E content of tissues of the rat pups. There were no significant differences (P > 0.05) in E content of plasma or liver tissue at birth in rat pups regardless of the maternal E status. Heart and lung tissue, however, were significantly higher (P < 0.05) in E concentration at birth in pups whose dams were fed the +E diets. Rat pups nursing -E dams had consistently low E content in each of the tissues throughout the postpartum period which did not differ from levels determined prior to nursing. Pups nursing +E dams had elevated E concentration in each of the tissues during the postpartum period. Liver tissue provided the most remarkable response in that E concentration increased approximately 30-fold within 4 days postpartum and then decreased abruptly. The results of these studies suggest a differential transfer of E to rat tissues during gestation. Net placental transfer of E to fetal liver appeared to be very low and was not influenced by marked differences in maternal dietary E. In contrast, preferential incorporation into heart and lung tissue during gestation was shown by the data. In all tissues, increased E content following birth was attributed to ingestion of colostrum and milk containing elevated amounts of the vitamin.
在这些研究中，使用了预先适应四种维生素E（E）和硒（Se）含量不同的实验性饮食之一的Long-Evans雌性带帽大鼠。基础饮食（-E -Se）的E（15 IU/kg）和Se（0.03 mg/kg）含量处于边缘水平。通过根据需要向基础饮食中添加dl-α-生育酚醋酸酯使其含量达到150 IU/kg或添加亚硒酸钠使其含量达到0.5 mg/kg，制备了另外三种饮食，即-E、+Se、+E-Se和+E +Se。大鼠交配后，所生幼崽用于在出生（哺乳前）至21日龄的产后间隔期提供血浆、心脏、肺和肝脏组织进行E分析。围产期母鼠的Se营养差异不影响幼鼠组织的E含量。无论母鼠的E状态如何，幼鼠出生时血浆或肝脏组织的E含量均无显著差异（P>0.05）。然而，其母鼠喂食+E饮食的幼鼠出生时心脏和肺组织的E浓度显著更高（P<0.05）。在整个产后期间，哺乳-E母鼠的幼鼠各组织中的E含量一直较低且与哺乳前测定的水平无差异。哺乳+E母鼠的幼鼠在产后期间各组织中的E浓度升高。肝脏组织的反应最为显著，即产后4天内E浓度增加约30倍，然后突然下降。这些研究结果表明，在妊娠期间E向大鼠组织的转移存在差异。E向胎儿肝脏的净胎盘转移似乎非常低，且不受母鼠饮食E的显著差异影响。相比之下，数据显示在妊娠期间E优先掺入心脏和肺组织。在所有组织中，出生后E含量的增加归因于摄入了含有较高量该维生素的初乳和乳汁。
