Objective To observe the effect of electroacupuncture(EA) of “Shuigou”(GV26) on the activities of sonic hedgehog(Shh) signaling molecules(Shh

Ptch

Smo

Gli and Gli2) in ischemic brain tissues in rats with cerebral ischemia(CI)

so as to explore its mechanisms underlying improvement of CI.Methods Male Wistar rats were randomly divided into blank control group(n=10)

sham operation group(n=90)

model group(n=90) and EA group(n=90). The CI model was established by occlusion of the right middle cerebral artery(MCAO). According to the postoperative time points of MCAO

the later three groups were further divided into 1

3

6

9

12 and 24 h

and 3

7 and 12 d subgroups

with 10 rats in each subgroup. EA(15 Hz

2 mA) was applied to GV26 for 20 min. The 1 h to 24 h subgroups were treated immediately after modeling

the 3-12 d subgroups treated one time a day. The neurological severity score(NSS

0 to 18 points) was used to evaluate the rats' neurological function

and TTC staining was employed to assess the cerebral ischemic volume(percentage of cerebral infarct volume

CIV). Western blot was employed to detect the expression of Shh

Ptch

Smo

Gli1 and Gli2 proteins in the ischemic cerebral tissue. Results Compared with the sham operation group

the NSS scores of the model group increased at all time points(P<0.01). The percentages of CIV of the model group from 3 h to 12 d were obviously higher than those of the sham operation group(P<0.01). The NSS scores at 3

7 and 12 d and the percentages of CIV at 1

3

7 and 12 d after MCAO were significant lower in the EA group than in the model group(P<0.05). The protein expression levels of Shh from 12 h to 12 d(i.e. 12 h

24 h

3

7 and 12 d)

Ptch from 6 h to 12 d

Smo from 9 h to 12 d

Gli1 at 9 h

12 h

and from 3 d to 12 d

Gli2 at 6

9 and 12 h

and 3 d were significantly higher in the model group than in the sham operation group(P<0.05

P<0.01)

while those of Shh at 3

7 and 12 d

Ptch from 24 h to 7 d

Smo from 12 h to 7 d

Gli1 from 24 h to 7 d

Gli2 at 12 h

3 and 7 d were significantly higher in the EA group than in the model group(P<0.05

P<0.01). No statistical significances were found between the sham operation and the blank control groups in all the indexes mentioned above(P>0.05).Conclusion EA of GV26 can improve neurological function and reduce infarct volume in MCAO rats

which may be related to its function in up-regulating the activities of Shh signaling pathway in the ischemic cerebral tissues.