Abstract： BACKGROUND: According to the thought "prevention of diseases", a conception of "strengthening the vital by acupuncture preconditioning (AP)" is suggested recently.OBJECTIVE: To investigate the effect of brain tissue extract after AP on cerebral ischemia-reperfusion injury.DESIGN: Random control experiment.SETTING: Institute of Acupuncture & Moxibustion and Massage, and Department of Anatomy and Embryology, Hubei College of Traditional Chinese Medicine.MATERIALS: Totally 102 adult Wistar rats were selected during the experiment, which was completed in the Institute of Acupuncture & Moxibustion and Massage of Hubei College of Traditional Chinese Medicine from September 2003 to July 2004. Among them, 20 rats were used to prepare cerebral tissue extract, and another 82 were used in the subsequent experiment.METHODS: The brain tissue extract was obtained from the rats which were given electroacupuncture at Shenshu (BL-23) and Baihui (DU-20).Totally 82 rats were randomly divided into 6 groups. Five rats in blank control group were taken as blank control, 15 in sham-operation control group were performed with sham operation, 16 in cerebral ischemia-reperfusion control group with cerebral ischemia-reperfusion, 16 in saline control group with the injection of saline intravenously firstly and then cerebral ischemia-reperfusion modeling, 15 in normal cerebral tissue extract control group with the injection of normal cerebral tissue extract intravenously firstly and then cerebral ischemia-reperfusion modeling, and 15 in AP cerebral tissue extract group with the injection of cerebral tissue extract intravenously firstly and then cerebral ischemia-reperfusion modeling.Intravenous injection was performed 2 hours and 1 hour before cerebral ischemic modeling, and each rat was injected twice with 1 mL/time. Brain tissue of the rats was taken ont 1, 3, 7 days after reperfusion respectively (or each group was divided into 3 subgroups with 5 rats in each) except those in blank control group. The blain tissue of rat in each group was selected at the relevant time points, and embedded with paraffin and cut into pieces. Cerebral histopathology was observed under the light scope (× 400)and the survival neurons were counted whose area was layer y of region Ⅰ in parietal cortex (inner cone).cortex.RESULTS: Two rats died during the experiment in cerebral ischemiareperfusion control group and saline control group respectively. Another Except blank control group and sham operation group, the brain sections of different time points in other groups showed scattering ischemic anoxic Count of survival neurons in layer Ⅴ of area I in parietal cortex: One day after reperfusion, survival nerve density of the brain ischemic reperfusion model group [(338.8±31.2)/mm2] was significantly lower than that of blank control group [(753.4±60.8)/mm2] (F=129.36, P ＜ 0.05); degeneration of the nerves became worse after reperfusion for 3 days and 7 days, but with no significant difference (F=1.76, P ＞ 0.05). There was no significant difference between the saline control group, normal brain tissue extract group and brain ischemic reperfusion model group at different time points (F=1.76, P ＞ 0.05). Survival neuron density in group of brain tissue extract after AP at the three time points was significantly higher than that in brain ischemic reperfusion model group [(438.1±41.0), (338.8±31.2)/mm2,(296.4±27.1), (124.8±13.4)/mm2; (269.5±30.4), (1.324±0.157)/mm2;F=129.36, P ＜ 0.05].CONCLUSION: Injection of the brain tissue extract after AP at Shenshu (BL-23) and Baihui (DU-20) into the celiac cavity of rats could obviously reduce the subsequent neuron loss induced by brain isehemia-reperfusion and protect brain from ischemia-reperfusion injury.