慢病毒介导的Cdh1-siRNA在大鼠全脑缺血再灌注损伤后的表达及功能

Expression and function of lentivirus-mediated Cdh1-siRNA in global brain ischemia-reperfusion damage of rats

目的:探讨慢病毒介导RNA干扰Cdh1的表达对全脑缺血再灌注损伤的影响。方法:将150只雄性SD大鼠随机分成生理盐水组(A组)、空慢病毒组(B组)和重组慢病毒组(C组)各50只。分别给予3组大鼠注射生理盐水、空慢病毒和重组慢病毒,注射3d后采用改良4-VO法建立SD大鼠全脑缺血再灌注损伤模型,采用荧光定量PCR检测大鼠海马组织Cdh1mRNA表达,Western blot检测Cyclin B的变化,TUNEL法检测海马CA1区凋亡细胞指数(AI)。于全脑缺血再灌注术后第7天行Morris水迷宫测试认知功能的变化。结果:C组Cdh1mRNA表达明显低于A、B组(P<0.05);AI值及Cyclin B表达均明显高于A、B组(P<0.05);水迷宫测试结果显示,术后第9～11天各时间点C组的寻台潜伏期明显长于A、B组(P<0.05)。结论:细胞周期末期分裂促进复合物及其调节亚基Cdh1可能通过Cyclin B堆积介导缺血性神经元的凋亡。

Objective：To investigate the expression and function of Cdhl-siRNA in cerebral ischemia-reperfusion injury of rats. Methods：All 150 male Sprague-Dawlcy rats were randomly divided into normal saline group （group A, n = 50）, lentivirus vector group （group B, n = 50） and recombinant lentivirus group （group C, n = 50）. The rats in 3 groups were injected with normal saline, lentivirus vector and recombinant lentivirus respectively. At the 3rd day after injection, cerebral ischemia-reperfusion injury model of rat was established by modified four-vessel occlusion （4- VO） method. The expression of Cdhl mRNA and Cyelin B was detected by quantitative real-time PCR and Western blotting. Apoptosis index （AI） was examined by using TUNEL staining method and the behavior was evaluated with Morris water maze test at the 7th day. Results： The expression of Cdhl mRNA in group C was significantly lower than that in groups A and B （P〈0.05） ,but that of Cyclin B and the levels of AI in group C were significantly higher than those in groups A and B （P〈0.05）. In addition,Morris water maze tests revealed that the latent period of see- king the platform in group C was longer than that in the other two groups from the 9th to llth day after surgery. Conclusion： Cyclin B accumulation by APC-Cdhl may mediate apoptosis of ischemic neurons.