Objective:To observe the effect of electroacupuncture(EA)on serum nitric oxide(NO)and plasma endothelin(ET)contents in cerebral ischemia/reperfusion(CI/R)rats.Methods:Fifty-five SD rats were evenly randomized into sham-operation(sham-op)

model

EA

acupoint-control(acu-con)and non-acupoint(non-acu)-con groups.CI/R model was produced by occlusion of the basilar artery and bilateral common carotid arteries and reperfusion.EA(10 Hz

1.5-3 V

duration of 0.6 ms)was applied to left “Jianyu”(LI 15)

“Waiguan”(TE 5)

etc.for EA group

left “Qinglengyuan”(TE 11)

“Lingdao”(HT 4)

etc.for acu-con(being not used for CI in clinic)group

and the mid-points between left “Tianquan”(PC 2)and “Quze”(PC 3)

PC3 and “Ximen”(PC 4)

etc.for non-acu-con group.Carotid venous blood was collected 30 min after CI and after CI/R respectively for analyzing serum NO content with nitrate reductase(NR)method and plasma ET content with radioimmunoassay

and the brain was taken for detecting its water content and Ca2+ content with flame atomic absorption method.Results:Compared with sham-op group

serum NO contents of model group 30 min after CI and CI/R

that of EA group 30 min after CI

acu-con group 30 min after CI/R decreased significantly(P<0.05)

and plasma ET content of model group 30 min after CI/R increased considerably(P<0.05).While compared with model group

serum NO content of EA group 30 min after CI/R increased significantly(P<0.05)and plasma ET of EA group decreased significantly(P<0.05).Serum NO level of acu-con group 30 min afterCI/R was markedly lower than that of EA group at the same time course.In comparison with sham-op group

Ca2+ contents of model group and acu-con group and water cntent ratio of the brain tissue of model group increased significantly(P<0.05)

while compared with model group

Ca2+ content of EA group decreased remarkably(P<0.05)

and Ca2+ of acu-con group was significantly higher than that of EA group(P<0.05).No significant differences were found between acu-con and non-acu-con groups in the aforementioned indexes(P>0.05).Conclusion:EA of commonly-used acupoints can revise CI/R induced decrease in serum NO level and increase in plasma ET and cerebral Ca2+ significantly at the early period of CI/R

which may contribute to its favorable effects in the treatment of CI.