OBJECTIVE:Electroacupuncture effect on neurological behavior and the expression of tyrosine kinase Janus kinase 2(JAK 2) of ischemic cortex in rats with the focal cerebral ischemia were investigated in this study.METHODS:The model of focal cerebral ischemia was established by the heat-coagulation induced the occlusion of the middle cerebral artery.The electro-acupuncture was applied on Baihui(GV 20) and Dazhui(GV 14),and AG490 was applied by intracerebroventricular infusion.The expressions of JAK2 mRNA and phospharylatedJAK2(p-JAK2) in the ischemic cortex were observed by in situ hybridization and western blotting.RESULTS:The expressions of JAK2 mRNA and p-JAK2 were rarely found in sham surgery group.In model group,the expression of JAK2 mRNA and JAK2 phosphorylation had increased.After 1 day of cerebral ischemia,the expression had reached its peak.After cerebral ischemia,the expressions of JAK2 mRNA and p-JAK2 were consistent with the neurological deficit score.Electroacupuncture treatment and AG490 intervention were able to improve the neurological deficit score after cerebral ischemia,and down-regulate the expressions of JAK2 mRNAand JAK2 phosphorylation.CONCLUSION:After cerebral ischemia,the excessive expressions of JAK2 and the JAK2 phosphorylation would be one of mechanisms by which the brain injury got worse.The therapy of electro-acupuncture could reduce the expression of JAK2,and inhibit JAK2 phosphorylated activation,so as to block the abnormal activation of signal transduction pathway which was induced by JAK2.