維生素A補充飼料對大鼠肝臟細胞色素酵素P450 3A蛋白質的影響

Effect of Vitamin a Supplemented Diet on Cytochrome P450 3A Protein in Liver Microsomes of Rats

本實驗目的為探討大鼠短期餵予維生素A補充飼料，對肝微粒體CYP3A蛋白質含量的影響。採用平均體重為141.5±7.0公克的Wistar公鼠12隻，先餵予AIN-76生長飼料三週後的平均體重約為295.3±20.4公克。將動物隨機分成兩組，其中一組繼續餵予AIN-76生長飼料（C組），另一組則餵予維生素A補充飼料（A組，維生素A含量為正常飼料的10倍），飼養期為一週。大鼠終體重達到平均324公克左右，各器官重量包含肝臟、腎臟、肺臟、心臟、睪丸、脾臟等與副睪脂肪重量於兩組間皆無顯著差異。肝臟視網醇（維生素A）濃度以A組顯著增加，約為C組的2.8倍，但是血漿中的視網醇濃度於兩組間並無顯著差異。在肝微粒體細胞色素酵素蛋白質方面，不管是CYP3A1或CYP3A2，其蛋白質表現含量於兩組間皆無顯著差異。從本實驗得知，十倍量維生素A的補充飼料對動物體重與器官皆無不良影響，同時也不會顯著增加肝微粒體細胞色素酵素CYP3A1與CYP3A2的蛋白質含量。

To study how the content of cytochrome P450 3A protein is affected by dietary vitamin A supplementation in short period, 12 male Wistar rats (142.5±7.0) were fed a control diet for 3 wk, and then randomly divided to 2 groups. The rats of 2 groups were fed with control diet (C group) and vitamin A supplemented diet (A group) separately for 1 wk. The final body weights of two groups were about 324g, and the organ weights (liver, kidney, lung, heart, testis, spleen and epididymal fat pad included) showed no significant difference between the two groups. The A group showed significantly higher retinol concentration in liver at about 2.8 fold in that of C group. But plasma retinol between the two groups showed no significant difference. The CYP 3A protein levels in the liver microsome also showed no significant difference between the two groups. Thus, the vitamin A supplemented diet could increased the retinol concentration in rat liver but showed no effects on the protein levels of CYP3A1 or CYP3A2 in liver microsome of rats.