摘要目的 观察针刺预处理对老年大鼠短暂性缺血/再灌注损伤后海马CA1区神经元凋亡的影响.方法 健康老年雄性Wistar大鼠120只,随机分为四组每组30只.组Ⅰ(单纯脑缺血/再灌注组):四动脉阻断法全脑缺血4 min建立老年大鼠全脑缺血模型;组Ⅱ(针刺预处理后脑缺血/再灌注组):连续5 d对百会穴实施穴位针刺预处理(疏密波,强度1mA,频率15 Hz),每天持续30 min,然后建立伞脑缺血模型;组Ⅲ(单纯针刺预处理组):仅针刺百会穴30 min/d,持续5 d;组Ⅳ(假手术组),仪暴露4条动脉,不缺血.每组分别于缺血后12 h、1、2、3和7 d各随机处死6只大鼠,随机抽取一只动物提取海马CA1区脑组织作透射电镜观察神经元超微结构,余下的5只光镜下观察海马神经元形态和凋亡细胞,监测Caspage-3蛋白表达.结果 各组于光镜和电镜下均可见凋亡神经元,与针刺对照组(再灌注2 d时6.7个±0.8个)和假手术组(再灌注2 d时7.2个±0.7个)相比,脑缺血再灌注组和针刺预处理后脑缺血再灌注组细胞凋亡数和Caspase-3表达阳性细胞数均显著增多,再灌注2 d后达峰值,差异有统计学意义(P<0.01);与脑缺血再灌注组(再灌注2 d时44.5±2.0比78.8±4.5)相比,针刺预处理后脑缺血再灌注组细胞凋亡数(冉灌注2 d时30.6±2.7个)和Cagpage-3表达阳性细胞数(再灌注2 d时43.8±2.4个)显著减少,差异有统计学意义(P<0.01).结论 针刺预处理可通过调控caspase-3蛋白的表达对老年大鼠短暂脑缺血再灌注损伤起到的保护作用.

abstractsObjective To investigate the effects of acupuncture pre-conditioning on apoptosis in hippocampal neurons following ischemia-reperfusion injury in aged rats. Methods A total of 120 senile male Wistar rats aged 19-21 months (corresponding to 60-year-old human being) weighting 550-710 g were randomly divided into 4 groups (n = 30 each). Cerebral ischemie group: 4-vessel-block was conducted for 4 minutes to establish cerebral ischemie models; Acupuncture pre-eonditioning group: electroacupuneture was applied at acupoint Baihui ( GV20 ) with a frequency of 15 Hz and 2 mA for 30 minutes once daily for 5 days. Then the rats received 4-vessel-block for 4 minutes; Sham-operation group: 4 vessels were exposed; Sham-acupuncture group: only eleetroaeupuncture for 5 days without operation. The rats were sacrificed at the end of predetermined duration of reperfusion 12 h, 1, 2, 3 and 7 d respectively. The brains were immediately harvested and hippocampal CA1 region was isolated for ( 1 ) light and electron microscopic examinations of hippoeampal neurons; (2) detection of apoptotic neurons (TUNEL) ; (3) determination of easpase-3 protein expression with SABC (streptavidin-biotin-poroxidase complex) immuno-histoehemieal technique. Results There were apoptotic neurons in all groups. The numbers of apoptotic neurons and positive neurons of caspase-3 significantly increased in the acupuncture pre-conditioning and cerebral isehemic groups versus the sham-acupuncture and sham-operation groups ( P < 0. O1 ). And the numbers of apoptotic neurons and positive neurons of caspase-3 significantly decreased in the acupuncture preconditioning group versus the cerebral ischemic group (P < 0.01 ). Conclusion Acupuncture preconditioning can decrease the neuronal apoptosis after ischemia-reperfusion injury through a lowered expression of caspase-3 protein in senile rats.