电针对颅脑损伤大鼠海马CA1区细胞凋亡的影响

Effects of Electro-Acupuncture on Apoptosis of Hippocampal CA1 Region in TBI Rats

目的:由海马神经元病理改变和细胞凋亡变化揭示电针对颅脑损伤大鼠海马CA1区细胞凋亡的影响。方法:60只SD大鼠随机分为假手术组、模型组和电针组,各20只。假手术组大鼠切开头皮,左侧颅骨钻孔后缝合头皮,不作外力打击;模型组使用改良的Feeny自由落体损伤装置制备颅脑损伤模型;电针组从造模第2天开始对大鼠进行连续14天的电针治疗。采用Morris水迷宫检测大鼠学习记忆能力。断头处死大鼠,取海马组织,HE染色镜下观察海马CA1区细胞形态,Western-blot检测海马组织CA1区凋亡蛋白caspase-3的表达量。结果:与假手术组相比,模型组和电针组的学习记忆能力评分降低,与模型组比较,电针组的评分显著升高。HE染色显示,模型组的大鼠海马神经细胞损伤严重,出现细胞肿胀、核固缩及空泡现象,电针组相对于模型组,细胞水肿、核固缩和空泡现象得到明显改善。Western-blot检测显示,模型组海马区凋亡蛋白caspase-3的表达量明显高于电针组。结论:颅脑损伤后对海马区域的损伤及其神经元凋亡的发生与caspase-3的激活有关,电针能阻滞caspase-3蛋白及其相关通路,有效防止细胞继续凋亡,并改善认知功能。

Objective:To investigate the effects of electro-acupuncture on apoptosis of hippocampal CA1 region in rats with traumatic brain injury(TBI) by observing the pathological changes and apoptosis of hippocampal neurons. Methods:60 SD rats were randomly divided into the sham operation group( n =20),the model group( n =20) and the electro-acupuncture group( n =20).In the sham operation group,the rat’s scalp was cut and sutured after drilling the left skull with no external force.The TBI model was established by using a modified Feeny free fall injury device.The rats in the electro-acupuncture group were treated with electro-acupuncture from the second day of modeling for 14 days.The learning and memory ability of rats was detected by Morris water maze.The morphology of hippocampal CA1 was observed by HE staining.The expression of caspase-3 in hippocampal CA1 was detected by Western-blot method. Results:Compared to those in the sham operation group,the learning and memory ability scores were significantly lowered after modeling;the scores were significantly increased after the electro-acupuncture treatment.HE staining showed that the hippocampal neurons were severely damaged,manifested with cell swelling,nuclear pyknosis and vacuolization,in the model group;the damages were significantly improved in the electro-acupuncture group.Western- blot analysis showed that the expression level of caspase-3 in the CA1 region of hippocampus in the model group was significantly higher than that in the electro-acupuncture group. Conclusion:The injury of hippocampus and the occurrence of neuronal apoptosis after traumatic brain injury are related to the activation of caspase-3.Electro-acupuncture can block caspase-3 protein and its related pathways,effectively prevent cells from continuing to apoptosis,and improve the function of recognition.