Objective: To observe the effects of acupuncture on cerebral structure and enzymatic activity after cerebral ischemia and to analyze the mechanisms of acupuncture in improving stroke. Methods: 35 SD rats were randomized into sham operation group (n=6)

ischemia group (n=9)

ischemia+reperfusion group (n=6)

acupuncture I group (n=6) and acupuncture II group (n=8). "Baihui"(GV 20) and bilateral "Quchi"(LI 11) were punctured and stimulated electrically with parameters of 7 Hz

0.7 V and duration of 30 min

which was respectively given after inducing cerebral ischemia (30 min) in acupuncture I group and 3 hr after ischemia+reperfusion in acupuncture II group. Cerebral ischemia model was established using four artery (bilateral vertebral arteries and bilateral common carotid arteries) occlusion and reperfusion method. Glutathione peroxidase (GSH px)

ATPase activity and malonyldialdehyde (MDA) in cerebral cortex and hippocampus tissues were assayed according to instructions of the reagent kits. Results: ① Following ischemia+reperfusion

cerebral tissue injury including neuron degeneration

death

gliocyte proliferation

etc was found in the hippocampus and cerebral cortex tissues in ischemia and ischemia+reperfusion groups

but in acupuncture II group no very apparent injury changes appeared. ②compared with the sham operation group

MDA contents in cellular plasma

membrane and mitochondria in ischemia group and ischemia+reperfusion group increased significantly in comparison with sham operation group (P<0.05

0.001). Following acupuncture (both acupuncture I and II groups)

MDA contents reduced significantly (P<0.001) compared with those of ischemia or ischemia+reperfusion groups (P<0.01). ③ Compared with the sham operation group

GSH px activity in cellular plasma

membrane and mitochondria increased in ischemia group (P<0.05); but compared with ischemia group

GSH px decreased very notably in ischemia+reperfusion group (P<0.01). After acupuncture

GSH px activity recovered basically compared with sham operation group. ④ Regarding ATPase activity

after ischemia and ischemia reperfusion

Na +

K + ATPase

Mg 2+ ATPase and Ca 2+ ATPase in plasma

membrane and mitochondria all lowered particularly in ischemia+reperfusion group (P<0.05). Following acupuncture (acupuncture II)

the 3 types of ATPase activity in cellular membrane and mitochondria recovered completely while the 3 types of ATPase activity in plasma was even evidently higher than that of sham operation group (P<0.001). Conclusion: Acupuncture of "Baihui"(GV 20) and "Quchi"(LI 11) can effectively reduce cerebral ischemia reperfusion induced neuronal degeneration

death and hyperactivity of membrane lipid peroxidation

attenuation of free radical clearing ability and energy metabolic abnormality in the ischemic cortex and hippocampus .