BACKGROUND: Long-term anti-depression treatment can promote the regeneration of hippocampal regeneration. Up-regulation of hippocampal regeneration can reverse or prevent against the injury of stress to cerebrum, especially to hippocampal structure and function. Therefore, promoting hippocampal neuronal regeneration may be a new strategy for treating depression and anxiety.OBJECTIVE: To observe the effect of electro-acupuncture at Du channel and meridian of foot-Taiyang on hippocampal neurons from model rats of depression.DESIGN: A randomized controlled animal experiment.SETTING: Department of Acupuncture and Moxibustion, Shenzhen Affiliated Hospital, Guangzhou University of Traditional Chinese Medicine.MATERIALS: Twenty-four Wistar rats, of either gender, aged 2 months old, weighing 200 - 220 g, were provided by the Animal Experimental Center, Guangzhou University of Traditional Chinese Medicine.METHODS: This experiment was carried out in the Clinical Molecular Biochemical Laboratory, Shenzhen Affiliated Hospital, Guangzhou University of Traditional Chinese Medicine between October 2006 and April 2007.①The involved rats were randomized into 4 groups according to body mass: blank control group,model group, electroacupuncture A group and electroacupuncture B group, with 6 in each. Rats in the blank control group were free to access to water, and were not given any intervention. Rats in the latter 3 groups were developed into rat depression models by chronic stress combined with feeding alone, and received 21-day unpredictable various stresses. Rats in the model group were euthanized at 14 days after modeling,and their brain tissues were harvested. Rats in the electroacupuncture A group were modeled, then points "Baihui" and "Shenting" were chosen, and given electroacupuncture, once a day, 20 minutes once. Rats in the electroacupuncture B group were modeled, then points "Baihui", "Shenting", "Xinshu"and "Ganshu" were chosen, and frequency and therapeutic time were the same as those of electroacupuncture A group. Rats in the latter 2 groups were also given electroacupuncture, and their brain tissues were harvested 14 days later.②Index evaluation: Neurons in hippocampal CA1 and CAS regions as well as dentate gyrus [neuron specific enolase (NSE)-positive cells] were counted by immunofluorescent technique. Each rat was weighted on the day of grouping and before execution at 35 days.MAIN OUTCOME MEASURES: Neuron amount in each hippocampal region and body mass of rats in each group.RESULTS: Twenty-four rats were involved in the final analysis.①Neuronal amount in each region of hippocampus: Neurons in the hippocampal CA1 and CA3 regions as well as dentate gyrus of rats in the model group were significantly less than those in the blank control group (P＜ 0.01). Neurons in hippocampal Caland CA3 regions as well as dentate gyrus of rats in the electroacupuncture A and B groups were more than those in the model group (P＜ 0.05).②Change in body mass of rats: Body mass increase of rats in the model group was less than that in the blank control group (P＜0.05), and body mass increase of electroacupuncture A and B groups was significantly more than that in the model group, respectively (P＜0.01).CONCLUSION: Electroacupuncture at Du channel and meridian of foot-Taiyang alleviates hippocampal neuronal injury of rats, and thereby, improves depression and promotes the increase of body mass of rats.