远隔缺血后适应对脑缺血/再灌注损伤保护作用的研究

目的 研究远隔缺血后适应（remote ischemic postconditioning,RIPostC）对脑缺血再灌注（ischemia/reperfusion,I/R）梗死体积及神经功能的影响.方法大鼠缺血2 h再灌注,即刻进行RIPostC 3个循环.神经功能评分采用Longa评分法、前肢踩空试验和12分评分法3种方法分别在脑缺血后8、24 h,3、7、14和30 d进行神经功能评分,并留取脑组织标本,进行苏木精-伊红（hematoxylin-eosin,HE）染色,计算脑梗死体积;部分大鼠应用头颅磁共振成像扫描进一步明确了大鼠的脑缺血状况.结果 Longa评分显示,与对照组相比,RIPostC组大鼠在7 d的神经功能评分降低,但差异无统计学意义;前肢踩空试验和12分评分法结果均显示：与对照组相比,RIPostC组大鼠3 d和7 d的神经功能评分显著降低,差异有统计学意义（P〈0.05）.脑梗死体积分析显示,RIPostC组与对照组相比,RIPostC组大鼠在脑缺血再灌注损伤后8和24 h、3和7 d的脑梗死体积均明显降低,差异具有统计学意义（P〈0.05）.结论 RIPostC可以减少大鼠脑缺血后8和24 h、3和7 d的脑梗死体积,改善脑缺血后3d和7d的神经功能评分,具有神经保护作用.

Effects of remote ischemic postconditioning on the cerebral ischemia/reperfusion injury and its mechanism

Objective To study the effects of remote ischemic postconditioning （RIPostC） on cerebral ischemia/reperfusion injury in rats. Methods Three cycles of RlPostC were given immediately after 2 hours of the ischemia in rats. We assessed neurological function before the sacrifice; magnetic resonance imaging（MRI） and hematoxylin-eosin staining were used for determining the infarct volumes at 8 hours, 24 hours, 3 days, 7 days, 14 days, and 30 days after the ischemia. Results Compared with the control groups, the neurological function scores were significantly decreased in R3d and R7d groups （P〈0.05）. The cerebral infarction volumes were significantly decreased in the R8h, R24h, R3d and R7d groups compared with the control groups（P〈0.05）. Conclusion RIPostC could reduce the cerebral infarction volumes at 8 h, 24 h, 3 d and 7 d after the cerebral ischemia, and improve the neurological defects in 3 days and 7 days after the cerebral ischemia in the model of middle cerebral artery occlusion（MCAO） in rats.