Objective To investigate the mechanism of electroacupuncture （EA） in treating Alzheimer＇s disease （AD） from aspect of mitochondria. Methods Twelve 8-month old SAMP8 mice were randomly divided into a model group （Group Mod, n=6） and an electroacupuncture group （Group EA, n=6）, and six 8-month old SAMR1 mice were selected as a control group （Group Cont）. Animals in Group EA was treated with EA at ＂Baihui＂ （百会 GV 20）, ＂Dazhui＂ （大椎 GV 14）, ＂Shenshu （肾俞 BL 23） and ＂Taixi＂ （太溪 KI 3） for 20 min, once daily with 20 days of treatments as a therapeutic course, lasting for 3 courses. Mice in the other two groups were fixed in the same way as those in Group EA at the same time without any treatment. After treatment, learning and memory abilities of the mice were measured by Morris water maze, activities of enzyme complex of hippocampal mitochondrial respiratory chain were measured by spectrophotometry, and levels of adenosine triphosphate （ATP） were detected by reverse phase high performance liquid chromatography （HPLC） method. Results Compared with Group Cont, the average escape latency in Group Mod was significantly prolonged, the residence time on the platform quadrant was shortened, the activities of enzyme complex Ⅰ, Ⅱ, Ⅲ and Ⅳ in hippocampal mitochondrial respiratory chain was decreased, and ATP contents was lessened in Group Mod. Compared with Group Mod, the average escape latency was significantly shortened, the residence time on the platform quadrant was lengthened, the activities of enzyme complex Ⅰ, Ⅱ, Ⅲ and Ⅳ in hippocampal mitochondria respiratory chain were significantly increased, and ATP contents were also increased in Group EA. Conclusion Electroacupuncture can elevate the activities of enzyme complex in hippocampal mitochondrial respiratory chain and ATP contents, and improve mitochondrial functions, which may be one of the underlying mechanisms of EA in treatment of AD.
