Zhu W, Wiggins R C, Konat G W
Department of Anatomy, West Virginia University School of Medicine, Morgantown 26506-9128.
J Neurosci Res. 1994 Feb 1;37(2):208-12. doi: 10.1002/jnr.490370206.
The effect of dexamethasone on the expression of proteolipid protein (PLP) and myelin-associated glycoprotein (MAG) genes was investigated in rat C6 glioma cells. The steady state level of the respective mRNAs was quantitated by Northern blot analysis. The treatment of cells with dexamethasone transiently upregulated the expression of both genes with peak mRNA levels of approximately 10-fold over control levels occurring at day 3 for the PLP gene and at day 5 for the MAG gene. The effect was directly related to the drug concentration in the range from 10(-9) to 10(-5) M. Combined exposure of the cells to dexamethasone and retinoic acid featured an additive effect on PLP gene expression, whereas MAG gene expression was depressed below detectability level. The dissimilarity in the response of the genes to dexamethasone and retinoic acid supports the contention that the genes are controlled by different mechanisms. Furthermore, the results indicate that the effects of dexamethasone and retinoic acid on the myelin genes are mediated by different regulatory pathways.
在地鼠C6胶质瘤细胞中研究了地塞米松对蛋白脂蛋白（PLP）和髓鞘相关糖蛋白（MAG）基因表达的影响。通过Northern印迹分析对相应mRNA的稳态水平进行定量。用地塞米松处理细胞可使两个基因的表达瞬时上调，PLP基因在第3天出现mRNA峰值水平，比对照水平高约10倍，MAG基因在第5天出现。该效应与10^(-9)至10^(-5)M范围内的药物浓度直接相关。细胞联合暴露于地塞米松和视黄酸对PLP基因表达具有累加效应，而MAG基因表达则降低至检测水平以下。这些基因对地塞米松和视黄酸反应的差异支持了基因由不同机制控制的观点。此外，结果表明地塞米松和视黄酸对髓鞘基因的作用是由不同的调节途径介导的。
