Abstract: Objective To explore the effect of electroacupuncture on activation of microglia in peri-infarct cortex after cerebral ischemia-reperfusion in rats. Methods 36 male Sprague-Dawley rats were randomly divided into sham group (n=12), model group (n=12) and electroacupuncture group (n=12). The latter two groups were occluded the left middle cerebral arteries with modified Longa's method for 2 hours and reperfused. The electroacupuncture group received electroacupuncture at Quchi (LI11) and Zusanli (ST36) acupoints for 3 days. The nerve cell damage in peri-infarct cortex was observed with HE staining, while the expression of ED1 was determined with immunohistochemical staining, and the expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and IL-6 were determined with Western blotting. Results The neurological deficits score improved significantly in the electroacupuncture group (P<0.05), with less nerve cell damage, less number of ED1 positive microglia (P<0.05) and less levels of TNF-α, IL-1β and IL-6 (P<0.05), compared with the model group. Conclusion The electroacupuncture at Quchi (LI11) and Zusanli (ST36) acupoints can protect brain from ischemia-reperfusion injury, which might be associated with inhibiting the microglial activation and proinflammatory response in peri-infarct cortex.

Key words: cerebral ischemia-reperfusion injury, electroacupuncture, microglia, inflammation, rats