大鼠脑缺血区皮层XIAP表达的动态变化及其意义

目的观察大鼠脑缺血区皮层XIAP表达的动态变化，探讨其在缺血后抗神经元凋亡过程中的可能机制。方法采用RT-PCR，免疫组化和western blot等方法分别从mRNA和蛋白水平测定脑缺血区皮层不同时间点XIAP表达的变化。结果XIAP转录水平和蛋白表达的改变呈时间依赖性；RT-PCR显示模型组大鼠在脑缺血后3h就有XIAP mRNA转录水平的明显上调，持续至24h后逐渐下降；免疫组化和western blot显示在脑缺血后6h有XIAP蛋白表达的增加，12h时XIAP蛋白表达至高峰（P〈0．01），48h基本恢复至缺血前水平。结论XIAP在脑缺血过程中可能具有抗凋亡作用。

Changes of expression of XIAP in rat brain after ischemic brain injury

Objective To observe the dynamic diversification of XIAP in rat brain after ischemic brain injury and to explore the mechanism of XIAP in the regulation of neuron apoptosis. Methods The expression level of XIAP in 80 rats after ischemic brain injury were serially measured with RT-PCR, immunohistochemistry and western blot 3,6,12,24,48 hours after the onset, and were compared with those of 50 normal controls. Results The present study provided evidence that XIAP levels are altered after cerebral ischemia and the changes were found to be temporally specific. The expression of XIAP mRNA increased excessively at 3 h after cerebral ischemia, began to decrease at 24 h; The expression of XIAP in cerebral cortex ischemia samples of the model group began to increase at 3 h after ischemia, reached apex at 12 h （P〈0. 01） and decreased at 48 h. Conclusions XIAP may contribute to anti-apoptosis in the course of pathophysiology of ischemic brain injury.