电针对SAMP8小鼠海马线粒体作用的研究

Observation on the Protective Effect of Electroacupuncture on Hippocampal Neuronal Mitochondria in SAMP 8 Mice

目的:观察电针对8月龄快速老化小鼠亚系(SAMP8)海马神经元线粒体超微结构及线粒体酶活性的影响,探讨电针治疗阿尔茨海默病(AD)的部分作用机制。方法:采用计算机随机的方法,将SAMP8小鼠24只分为模型组、电针组,每组各12只;8月龄抗快速老化小鼠亚系(SAMR1)12只作为空白组。电针"百会""涌泉"对电针组小鼠进行治疗,施以疏密波,频率2～100Hz,电压2～4V,强度以小鼠下肢轻微抖动为度,留针20min。每日1次,7d为1个疗程,共治疗3个疗程。治疗结束后,用Morris水迷宫测试各组小鼠空间学习记忆能力的变化,评价电针的治疗效应;用透射电镜观察海马神经元线粒体的超微结构;用分光光度法检测海马线粒体细胞色素C氧化酶(COX)的活性。结果:与模型组相比,电针组小鼠治疗后平均逃避潜伏期缩短,线粒体结构大致正常,嵴排列整齐,仅见部分轻度肿胀,线粒体体密度、面密度大于模型组,COX活性明显高于模型组(P<0.05,0.01)。结论:电针对AD学习记忆能力的改善可能与其减轻海马神经元线粒体超微结构损伤、提高线粒体COX活性、保护线粒体结构和功能、改善能量代谢有关。

Objective： To observe the influence of electroacupuncture （EA） on mitochondrial ultrastructure and mitochon-drial enzymatic activity in hippocampus of senescence accelerated mouse/prone 8 （SAMP 8） so as to explore its underlying mechanism in the treatment of Alzheimer＇s Disease （AD）. Methods： Twenty-four SAMP 8 mice were randomly and uniformly divided into model group and EA group and other 12 SAMR｜ mice were used as control group. EA （2- 100 Hz, 2-4 V） was applied to ＂Baihui＂ （GV 20） and ＂Yongquan＂ （KI 1） for 30 min. Changes of learning and memory ability were measured by Morris water maze test. The ultrastructure of hippocampal mitochondria was observed by using transmission electronic microscope. The activities of cytochrome C oxidase （COX） in hippocampal mitochondria were detected by spectrophotometric method. Results： In comparison with control group, the average escape latencies of model group were significantly longer from the 1^st day to the 5^th day in swimming test （P〈0.01）, while in comparison with model group, the escape latencies of EA group at the corresponding test day were markedly shorter （P〈0.05,0.01 ）, despite being still obviously longer than those of control group. The ultrastruc- ture of most mitochondria of EA group was basically normal, and the mitochondrial cristae were line up in order and presented mild swelling. Volume density and area density of mitochondria and COX activity of model group were significantly lower than those of control group, and these 3 indexes of EA group were significantly higher than those of model group（ P〈0.05, 0.01）. Conclusion： EA can improve AD rat＇s hippocampal mitochondrial structure and increase mitochondrial COX activity, which may contribute to its effect in improving the rat＇s learning and memory ability.