Objective To observe the effect of electroacupuncture(EA) of "Baihui"(GV 20) and "Dazhui"(GV 14) on the expression of gamma-glutamylcysteine synthetase(γ-GCS) protein and gene in the cerebral cortex in rats with cerebral ischemia-reperfusion(CI/R) injury

so as to explore its molecular biological mechanism underlying anti-oxidative stress.Methods A total of 30 male Sprague-Dawley rats were randomized into sham operation(sham

n=10)

model(n=10)

and EA(n=10) groups.CI/R model was established by right middle cerebral artery occlusion(modified Longa's thread occlusion method) for 2 hours and reperfusion for 24 hours.EA(3 Hz

1-3 mA) was applied to "Dazhui"(GV 14) and "Baihui"(GV 20) for 30 min.γ-GCS protein expression of the parietotemporal region of cerebral cortex was detected by immunohistochemistry and γ-GCS heavy subunit(γ-GCSh) mRNA and γ-GCS light subunit(γ-GCSI) mRNA expression levels were assayed by real-time quantitative polymerase chain reaction(RT-PCR).Results Compared with the sham group

the expression levels of γ-GCS protein in the pyramidal cell layer of the cerebral cortical parietotemporal region

and γ-GCSh mRNA and γ-GCSl mRNA

and the number of γ-GCS immuno-reaction positive cells had no remarkable changes in the model group(P>0.05)

while in comparison with the mo-del group

the expression levels of cerebral cortical γ-GCS protein

and γ-GCSh mRNA and γ-GCSl mRNA

and the number of γ-GCS immuno-reaction positive cells were increased considerably in the EA group(P<0.01

P<0.05).Conclusion EA of GV 20 and GV 14 can upregulate expression levels of γ-GCS protein

γ-GCSh mRNA and γ-GCSl mRNA of the cerebral cortical parietotemporal region in CI/R rats

which may contribute to its effect in protecting cerebral cortical cells from injury by clearing away excessive oxygen free radicals.