Tissue Discrimination between Dietary RRR-α- and all-rac-α-Tocopherols in Rats
Tissue Discrimination between Dietary RRR-α- and all-rac-α-Tocopherols in Rats
复制标题
大鼠膳食 RRR-α- 和全 rac-α-生育酚之间的组织区别
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
R. Madère
中科院分区：
文献类型：
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作者：
W. Behrens;R. Madère
在两项实验中，针对大鼠的血浆和组织测量了维生素E的天然形式RRR-alpha-生育酚与合成形式全-rac-alpha-生育酚之间的区别。在实验A中，动物以两种不同水平（0.035和0.200 g/kg饮食）饲喂RRR-alpha-或全-rac-alpha-生育酚乙酸酯，持续2.5个月。在实验B中，首先使大鼠耗尽维生素E 7周，然后喂食含有0.035 g/kg RRR-α-或全消旋-α-生育酚乙酸酯的饮食。在后一实验中，在3、7、17、31或45 d后处死大鼠，以研究辨别的时间过程。在两个实验结束时，测量血浆和组织中的α-生育酚水平。结果显示，大多数组织优先摄取天然RRR-a-生育酚。这种偏好很小，在某些组织中不会立即表现出来。在检查的组织中发现红细胞中的最大区别; RRR-alpha-生育酚饮食累积的alpha-生育酚水平是全外消旋-alpha-生育酚饮食累积的4至6倍。对于所有其他组织，该比值在1.0和1.5之间。这些结果表明，组织具有α-生育酚摄取机制，但该机制对RRR-a-生育酚并不完全特异。
The discrimination between the natural form of vitamin E, RRR-alpha-tocopherol, and the synthetic form all-rac-alpha-tocopherol was measured in two experiments for plasma and tissues of rats. In Experiment A, the animals were fed RRR-alpha- or all-rac-alpha-tocopheryl acetate at two different levels, 0.035 and 0.200 g/kg diet, for 2.5 mo. In Experiment B, rats were first depleted of vitamin E for 7 wk then fed a diet containing 0.035 g/kg diet of RRR-alpha- or all-rac-alpha-tocopheryl acetate. In the latter experiment, rats were killed after 3, 7, 17, 31 or 45 d to study the time course of the discrimination. At the end of both experiments, levels of alpha-tocopherol were measured in plasma and tissues. The results showed a preferential uptake of the natural RRR-alpha-tocopherol by the majority of the tissues. The preference is small and in some tissues is not immediately manifested. The greatest discrimination in the tissues examined was found in red blood cells; the levels of alpha-tocopherol accumulated with the RRR-alpha-tocopherol diet were four to six times that accumulated with all-rac-alpha-tocopherol diet. For all other tissues, this ratio was between 1.0 and 1.5. These results indicate that tissues have a mechanism for alpha-tocopherol uptake, but this mechanism is not entirely specific for RRR-alpha-tocopherol.