医学老鼠实验 (2)

电针对海洛因依赖大鼠海马神经细胞凋亡的影响

作者：潘莉潘贵书作者单位：（包头市蒙中医院内科,内蒙古包头014030；遵义医学院生理学教研室)

【摘要】目的：观察海洛因依赖大鼠海马细胞凋亡情况及电针的干预作用,为针刺戒毒提供一定的理论依据。方法:SD大鼠24只随机分为对照组和实验组；实验组按剂量逐日递增原则,每日2次、连续9天皮下注射海洛因，第10天用纳洛酮催促戒断，建立海洛因依赖模型,再经跳台实验测试筛选,分为电针组和非电针组,每组8只动物；非电针组继续给予海洛因维持剂量，电针组停止给药，处于自然戒断状态,同时选取“百会”、“大椎”进行电针治疗，每天1次，连续7天；采用TUNEL法、Envision免疫组化法检测3组大鼠海马区细胞凋亡情况及凋亡相关蛋白Bcl-2、Bax的变化。结果:与对照组比较,非电针组大鼠海马细胞凋亡指数显著升高(P<0.01),Bcl-2蛋白表达降低(P<0.01),Bax蛋白表达增加(P<0.01)；与非电针组比较,电针组大鼠海马区细胞凋亡指数显著降低(P<0.01),Bcl-2蛋白表达增加(P<0.01),Bax蛋白表达降低(P<0.01)。结论：电针促进Bcl-2表达、抑制Bax表达，可加速细胞修复、保护损伤脑组织、改善海洛因依赖大鼠学习记忆能力。

【关键词】海洛因依赖；细胞凋亡；海马；电针

The Effect of Electroacupuncture on Apoptosis of Hippocampal Neurocyte in Heroin-addict Rats PAN Li，PAN Guishu(Department of Cardiology, Baotou Hospital of Tranditional Mongolian and Chinese Medicine, Baotou 014040，China;Department of Physiology, Zunyi Medical College)

Abstract Objective:To observe the curative effect of electroacupuncture (EA) on apoptosis of hippocampal neurocyte, study its acupuncture treatment mechanism and provide some theoretical proofs for EA abstaining from narcotic. Methods: Twenty-four SD rats were randomly divided into the control group and the experimenting group. Heroin was injected subcutaneously twice a day for 9 days, with the dose increasing daily, in rats of the experimenting group. On the tenth day, the withdrawal signs precipitated by intraperitoned injection of naloxone was performed to establish the heroin-dependent model. The qualified rats were divided into the non-electroacupunctured group and the electroacupunctured group through the step-down test. Heroin was injected continuously according to the maintenance dose of non-electroacupunctured

group, while the electroacupunctured group was no longer given heroin. Meanwhile, Baihuiand and Dazhui points were chosen for electroacupunture treatment, once a day, for 7 days. Apoptosis of neurocytes in rats' hippocampus was measured with the method of TUNEL; Expression of Bcl-2 and Bax in neurocytes was measured with Envision immunohistochemical technique and results were analyzed by Imaging Analyzing System. Results: Compared with the control group, apoptosis index (AI) of neurocytes in hippocampus in non-electroacupunctured group was significantly higher, the expression of Bcl-2 decreased significantly, while the expression of Bax increased significantly. Compared with non-electroacupunctured group, apoptosis index (AI) of neurocytes in electroacupunctured group obviously decreased, the expression of Bcl-2 increased significantly，while the expression of Bax decreased significantly．Conclusion: Heroin can induce the apoptosis of hippocampus in rats by up-regulating the protein expression of Bax and down-regulating the protein expression of Bcl-2；Electroacupuncture can inhibit the apoptosis of hippocampus induced by heroin by up-regulating the protein expression of Bcl-2 and down-regulating the protein expression of Bax. Also, electroacupuncture can obviously improve the ability of learning and memory．

Key words Heroin-dependence；Apoptosis；Hippocampus；Electroacupuncture 海洛因为二乙酰吗啡，海洛因依赖在世界范围内成为一种严重的社会公共卫生问题，而其中枢机制则是解决临床预防和治疗的关键，但至今仍不清楚。脑内与学习记忆密切相关的结构如皮层和海马等，参与药物精神依赖的形成。脑功能成像研究表明，阿片成瘾戒断者通过回忆欣快经验引发心理渴求时，脑内与学习记忆有关的脑区如前额叶、海马、杏仁核等代谢活动明显增强。已有证据表明,皮质和海马直接参与信息的贮存。目前的研究证实了海洛因依赖致脑损伤中有细胞凋亡的存在，并且有依据表明调控神经细胞凋亡可减轻海洛因依赖脑损伤的程度。本实验旨在探讨细胞凋亡调控基因Bcl-2和Bax在海洛因依赖大鼠海马的表达以及电针对其表达的影响，为进一步探讨海洛因依赖的学习记忆机制提供理论依据。

1 材料与方法

1.1 材料实验动物选择健康SD大鼠24只，雌雄不拘，体重180～220g，由重庆第三军医大学动物实验中心提供（生产许可证号SCXK(渝)20020003）。大鼠分笼饲养,自由饮水、进食。