大鼠脑缺血再灌注后Cathepsin D和caspase．9表达的动态变化

目的：探讨大鼠缺血再灌注后溶酶体组织蛋白酶D（Cathepsin DCD）、caspase-9在不同时段蛋白质及mRNA表达变化。方法：将60只SD大鼠随机分为三组：正常组（10只），假手术组（10只），脑缺血再灌注组（40只），线栓法制备大脑中动脉梗死模型（MCAO），免疫组化及RT—PCR法分别检测CathepsinD、caspase-9的蛋白和mRNA表达。结果：与正常组和假手术组比较，模型组大鼠脑缺血再灌注损伤后6h Cathepsin D的蛋白和mRNA表达明显增强（P〈0．05），24h达高峰，48h仍保存高水平。caspase．9蛋白和mRNA6h开始明显升高，12h达高峰，此后缓慢下降，但48h组仍显著高于对照组（P〈0．05），结论：Cathepsin D、caspase．9在大鼠脑缺血再灌注后表达增强，溶酶体可能参与了脑缺血再灌注损伤后神经细胞凋亡的过程。

Changes of CathepsinD and caspase-9 Expression in Rats after Cerebral Ischemia-Reperfusion

Objective：To study the changes of the protein and mRNA of Cathepsin D and caspase-9 expression in different time point in rat after cerebral ischemia-reperfusion. Methods：60 SD rats were randomly divided into three groups： normal group （n=10）, sham-operation group （n=10）, cerebral isehemia-reperfusion group （n=40）, prepared by suture middle cerebral artery infarction model （MCAO）, the expression of the protein and mRNA of Cathepsin D and caspase-9were respectively evaluated by methods of immunohistoehemistry and RT-PCR. Results：compared with normal group and sham-operated group , The expression level of the protein and mRNA of Cathepsin D and easpase-9 in the rats of model group increased significantly 6 hour ,the formers got to their peak 24h while the latters got to their peak 12h ,both of them kept a high level on 48h. Conclusions ：The expression of Cathepsin D and caspase-9 after ischemia-reperfusion is high, Lysosomes may be involved in the process of neuronal apoptosis in the brain after ischemia-reperfusion injury