Objective To observe the effect of electroacupuncture(EA) intervention on expression of Slit 2 and its transmembrane receptor Robo 1 in the cortex tissue of cerebral infarction rats so as to study its mechanism underlying improvement of cerebral ischemia.Methods Ninety male Sprague Dawley rats were randomly divided into control group(n=10)

model group(n=40) and EA group(n=40)

and the latter two groups were further randomized into four subgroups: 1 d

3 d

7 d

and 14 d(n=10 in each subgroup) according to the cerebral ischemia duration.Cerebral infarction model was established by occlusion of the middle cerebral artery(MCAO).EA(80-100 Hz

1-3 mA) was applied to bilateral "Neiguan"(PC 6) and "Zusanli"(ST 36) for 30 min

once daily for 1 d

3 d

7 d

and 14 d

respectively.The animals' neurological defect was assessed using Zea-Longa scoring.The expression of Slit 2 and Robo 1 proteins in the cerebral cortex on the ischemic side was assayed using immunohistochemistry and Western blotting

respectively.Results In comparison with the control group

the neurological score was significantly higher in the model group(P<0.05)

and reduced considerably on day 7 and 14 after MCAO in the EA group compared with the model group(P<0.05).Immunohistochemical results showed that in comparison with the control group

the immunoactivity levels of cerebral Slit 2 and Robo 1 were remarkably upregulated on day 1

3 and 7 after MCAO in the model group(P<0.05

P<0.01)

and backed to the control levels on day 14(P>0.05).While compared with the model group

the immunoactivity levels of cerebral Slit 2 and Robo 1 were further obviously upregulated on day 1

3

7 and 14 after cerebral ischemia in the EA group(P<0.05

P<0.01).The results of Western blotting about the expression levels of cerebral Slit 2 and Robo 1 proteins were nearly the same to those of immunohistochemical outcomes in the 4 subgroups apart from that the expression levels of both Slit 2 and Robo 1 proteins were still obviously higher on day 14 after MCAO in the model group(P<0.01).Conclusion EA intervention can significantly improve cerebral ischemia rats' neurological function and obviously upregulate the expression of cerebral Slit 2 and Robo 1 proteins

which may be one of the mechanisms of EA therapy for relieving cerebral infarction in clinic.