Objective To observe the effect of electroacupuncture(EA) intervention on expression of signal transducer and activator of transcription 3(STAT 3) in the focal ischemic cerebral tissue

so as to study its mechanism underlying improving ischemic stroke.Methods A total of 150 SD rats were randomized into sham operation(control) group

cerebral ischemia(CI) model(model) group and EA group which were further randomly divided into 2 hour(2 h)

1 day(1 d)

3 d

1 week(1 W) and 3 W subgroups(n=6/subgroup for immunohistochemistry

n=4/subgroup for Western blot).CI model was established by occlusion of the middle cerebral artery with electro-coagulation method.EA(3 Hz/20 Hz

2-3 V) was applied to "Baihui"(GV 20) and "Dazhui "(GV 14) for 30 min.The expression of cerebral STAT 3 was detected by immunofluorescence histochemistry and laser-confocal microscopy

and Western blot

separately.Results Compared with the control group

cerebral STAT 3 immunofluorescence intensity values at the time-points of 2 h

1 d

3 d and 1 W

STAT 3 protein expression levels at the time-points of 2 h

1 d and 3 d in the model group were increased significantly(P<0.001

P<0.05).After acupuncture intervention

cerebral STAT 3 immunofluorescence intensity values at the time-points of 1 d

3 d

1 W and 3 W

STAT 3 protein expression levels at the time-points of 1 d

3 d and 3 W in the EA group were down-regulated considerably(P<0.001

P<0.01

P<0.05).No significant differences were found between the control and model groups in STAT 3 immunofluorescence intensity at 3 W

and in STAT 3 protein expression levels at 1 W and 3 W

and between the EA and model groups in STAT 3 immunofluorescence intensity at 2 h

and in STAT 3 protein expression at 2 h

3 d and 1 W(P>0.05).Conclusion EA therapy can down-regulate the expression level of STAT 3 protein in the regional ischemic cerebral tissue in cerebral ischemia rats

which may contribute to its efficacy in the treatment of acute and chronic ischemic stroke.