肢体远隔缺血后处理联合电针后处理对大鼠局灶性脑缺血再灌注损伤的影响

Effect of remote limb ischemic postconditioning combined with electro-acupuncture postconditioning on focal cerebral ischemia-reperfusion injury in rats

目的 评价肢体远隔缺血后处理联合电针后处理对大鼠局灶性脑缺血再灌注损伤的影响.方法 雄性SD大鼠70只,6周龄,体重220～ 250 g,采用随机数字表法分为5组（n=14）：假手术组（S组）、缺血再灌注组（I/R组）、肢体远隔缺血后处理组（RLIP组）、电针后处理组（EAP组）和肢体远隔缺血后处理联合电针后处理组（LRIP＋EAP组）.采用大脑中动脉线栓阻塞120 min时再灌注的方法制备局灶性脑缺血再灌注损伤模型.于再灌注即刻实施肢体远隔缺血后处理,对双侧股动脉实施3次15 min阻断15 min开放;于再灌注即刻实施电针后处理,电针刺激大椎穴和百会穴,选用疏密波,频率15 Hz/2 Hz,强度1 mA,时间30 min.再灌注24 h时进行神经功能缺陷（NDS）评分,然后处死,取脑组织,测定脑梗死体积百分比,Nissil染色,光镜下观察海马CA1区病理学结果,进行存活神经元计数,并测定凋亡指数（AI）.结果 与S组比较,其余4组NDS评分、脑梗死体积百分比、AI增加,存活神经元计数降低（P＜0.05）;与I/R组比较,RLIP组、EAP组和RLIP＋EAP组NDS评分、脑梗死体积百分比和AI降低,存活神经元计数升高（P＜0.05）;与RLIP组和EAP组比较,RLIP＋EAP组NDS评分、脑梗死体积百分比和AI降低,存活神经元计数升高（P＜0.05）.结论 肢体远隔缺血后处理联合电针后处理减轻大鼠局灶性脑缺血再灌注损伤的效果优于单独一种方法.

Objective To evaluate the effect of remote limb ischemic postconditioning （RLIP） combined with electro-acupuncture postconditioning （EAP） on focal cerebral ischemia-reperfusion （I/R） injury in rats.Methods Seventy male Sprague-lDawley rats,weighing 220-250 g,were randomly assigned into 5 groups （n =14 each） using a random number table：sham operation group （group S）,group I/R,RLIP group,EAP group and RLIP combined with EAP group （group RLIP ＋EAP）.Focal cerebral I/R was induced by middle cerebral artery occlusion （MCAO）.MCAO was maintained for 120 min.The animals were subjected to 3 cycles of 15 min ischemia of bilateral hind limbs followed by 30 s reperfusion starting from onset of reperfusion.Dazhui and Baihui acupoints were stimulated with electric stimulator （frequency 15 Hz/2 Hz,intensity 1 mA） for 30 min starting from onset of reperfusion.Neurological deficit scores （NDSs） were evaluated at 24 h of reperfusion.The animals were then sacrificed and brains were removed to measure the infarct size and for microscopic examination of pathological changes in hippocampal CA1 region.The number of survival neurons was counted.The apoptosis in neurons was determined by TUNEL.Apoptosis index was calculated.Results Compared with group S,the NDSs,percentage of cerebral infarct size and AI were significantly increased,and the number of survival neurons was decreased in the other four groups.Compared with group I/R,the NDSs,percentage of cerebral infarct size and AI were significantly decreased,and the number of survival neurons was increased in EAP,RLIP and RLIP＋EAP groups.Compared with RLIP and EAP groups,the NDSs,percentage of cerebral infarct size and AI were significantly decreased,and the number of survival neurons was increased in group RLIP＋ EAP.Conclusion The combination of RLIP and EAP provides better efficacy than either alone in attenuating focal cerebral I/R injury in rats.