Schäfer H, Elmadfa I
Ann Nutr Metab. 1984;28(5):297-304. doi: 10.1159/000176819.
In experiments with male wistar rats the influence of dl-alpha-tocopherol as well as dl-gamma-tocopherol on both the respiration of liver mitochondria and membrane lipid peroxidation has been investigated. For a test period of 8 weeks the animals were fed isoenergetic diets containing either no vitamin E or 46 mg d-alpha-tocopherol equivalents/kg diet as dl-alpha-tocopherol (60 ppm) or dl-gamma-tocopherol (480 ppm). The diets contained 6% of a synthetic triglyceride mixture rich in polyunsaturated fatty acids (about 60%). The measurements of the P/O ratios and corresponding respiratory control index (RCI) values for several substrates (alpha-ketoglutarate, malate/glutamate, succinate) indicated that under vitamin E-deficient conditions the mitochondria showed an increased respiratory intensity accompanied with an elevated lipid peroxidation. The oxidative phosphorylation itself was not affected. These deficiency symptoms could be normalized by the applied amounts of both tocopherols. In this respect dl-gamma-tocopherol showed a more distinct bioactivity than previously proposed. Based on the investigated parameters we calculated for dl-gamma-tocopherol an average bioactivity of 28% compared to that of dl-alpha-tocopherol.
在对雄性Wistar大鼠进行的实验中，研究了dl-α-生育酚以及dl-γ-生育酚对肝脏线粒体呼吸和膜脂质过氧化的影响。在为期8周的测试期内，给动物喂食等能量饮食，这些饮食要么不含维生素E，要么含有46毫克d-α-生育酚当量/千克饮食的dl-α-生育酚（60 ppm）或dl-γ-生育酚（480 ppm）。饮食中含有6%富含多不饱和脂肪酸（约60%）的合成甘油三酯混合物。对几种底物（α-酮戊二酸、苹果酸/谷氨酸、琥珀酸）的P/O比值和相应的呼吸控制指数（RCI）值的测量表明，在维生素E缺乏的条件下，线粒体显示出呼吸强度增加，同时脂质过氧化升高。氧化磷酸化本身未受影响。两种生育酚的应用量均可使这些缺乏症状恢复正常。在这方面，dl-γ-生育酚显示出比先前提出的更明显的生物活性。根据所研究的参数，我们计算出dl-γ-生育酚与dl-α-生育酚相比的平均生物活性为28%。
