短暂前脑缺血小鼠海马脑红蛋白表达的动态变化

Kinetic Change in the Expression of Neuroglobin in Mouse Hippocampus after Transient Forebrain Ischemia

研究了小鼠短暂前脑缺血再灌注后不同时相点脑红蛋白表达的动态变化及其意义。用夹闭双侧颈总动脉的方法建立C57BL/6小鼠缺血再灌注动物模型;采用RT-PCR及Western blotting方法检测各组小鼠海马组织中脑红蛋白在转录和翻译水平表达的动态变化。结果显示,脑红蛋白在mRNA水平表达的动态变化为:与假手术对照组(100±0.00)比较,再灌注后6h(132.59±28.26,P<0.05)开始升高;24h(157.36±13.85,P<0.001)达高峰;48h(146.55±23.17,P<0.01)开始下降;72h(118.42±34.23,P>0.05)基本恢复至正常水平。脑红蛋白在蛋白水平表达的动态变化为:与假手术对照组(100±0.00)比较,再灌注后6h(111.46±23.54,P>0.05)轻微升高,24h(141.25±32.12,P<0.01)达高峰,48h(138.02±19.68,P<0.05)开始下降,72h(119.29±35.18,P>0.05)基本恢复至正常水平。结果提示,脑缺血再灌注各时相点的脑红蛋白mRNA及蛋白表达水平均增加,可能是机体的应激反应,但持续时间较短(48h以内)。

The kinetic changes in the expression of neuroglobin（NGB）in mouse hippocampus after transient forebrain ischemia-reperfusion at different time points were investigated and the significance of these changes was discussed.The C57BL/6 mice model of ischemia-reperfusion was established by transient occlusion double side carotid artery under micromanipulation.RT-PCR was used to detect the dynamic changes in NGB mRNA expression（transcription level）and Western blotting was used to detect the dynamic changes in NGB protein expression（translation level）.The results demonstrated that,compared with sham-operated control group（100±0.00）,the expression of NGB mRNA increased initially at 6 h after reperfusion（132.59±28.26,P 〈0.05）,reached a peak at 24 h（157.36±13.85,P〈0.001）,degraded since 48 h（146.55±23.17,P〈0.01）and the expression of NGB mRNA dramatically dropped down nearly to normal level at 72 h（118.42±34.23,P〉0.05）after reperfusion.A similar tendency was found in the expression of NGB protein compared with sham-operated control group（100±0.00）.The NGB protein increased little at 6 h after reperfusion（111.46±23.54,P〉0.05）,reached a peak at 24 h（141.25±32.12,P〈0.01）and degraded since 48 h（138.02±19.68,P〈0.05）.The expression of NGB protein dramatically dropped down to nearly normal level at 72 h（119.29±35.18,P〉0.05）after reperfusion.The results indicate that the increased expression of NGB mRNA and protein at different phase point after reperfusion might be an irritable protective effects against ischemia-reperfusion brain damage,but the duration of its expression is short（within 48 h）.