脑缺血后髓鞘基因表达变化的规律

mRNA expression change of myelin gene in hippocampus following cerebral ischemia

目的从髓鞘碱性蛋白(MBP)mRNA、髓鞘少突胶质糖蛋白(MOG)mRNA等髓鞘基因表达的角度,探讨脑缺血大鼠髓鞘损伤的变化规律。方法采用SD大鼠四血管闭塞急性全脑缺血模型,随机分为2 d、4 d、7 d、14 d和28 d五个时间点及假手术组,每组8只;用逆转录聚合酶链式反应(RT-PCR)观察海马组织中MBP mRNA、MOG mRNA表达的变化。结果脑缺血后2 d海马组织中MBP mRNA、MOG mRNA表达水平即已降低,至7 d时降低显著,并持续至28 d时达到高峰。与假手术组比较,大鼠海马组织内MBP mRNA、MOG mRNA表达于再灌流后7 d、14 d、28 d差异具有统计学意义(P<0.05)。结论随着脑缺血-再灌流时间延长,大鼠海马组织MBP mRNA、MOG mRNA表达逐渐降低,呈现时间依赖性。

Objective To study the mRNA expression of myelin basic protein （MBP） and myelin oligodendroglia glyeoprotein （MOG） in hippocampus of rats following global brain ischemia. Method The four- vessel occlusion animal model in the Sprague-Dawley rats was used in this study, The mRNA expression levels of MBP and MOG in the hippocampus of rats were analyzed by reverse transcription polymerase chain reaction （ RT- PCR） at day 2, 4, 7, 14 and 28 days after global brain ischemia, There were eight rats at each time-point and sham operated group. Results The mRNA expression of both MBP and MOG in hippocampus of rats decreased at 2 days after global brain ischemia, The gene expression of myelin gene decreased significantly at 7 days and it reached to the lowest level at 28 days. Compared with sham operated group, the gene expression of MBP and MOG in hippocampus of rats decreased significantly at 7, 14 and 28 days after global brain ischemia （ P 〈 0.05）. Conclusions The down-regulation of MBP mRNA and MOG mRNA was time dependent in hippocampus following transient global ischemia in rats.