Objective To observe the effect of electroacupuncture(EA) of bilateral "Futu"(LI 18) on the immunoactivity of substance P(SP)

NK-1 receptor(R)

cyclooxygenase-1(COX-1)

5-HT 1 AR and 5-HT 2 AR in the cervical spinal dorsal horn of rats with neck incision pain

so as to explore its underlying mechanism in relieving incision pain.Methods A total of 40 Wistar rats were randomly divided into control

model(incision pain)

EA-Futu(LI 18)

and EA-Zusanli(ST 36)-Yanglingquan(GB 34

EA-ST 36-GB 34) groups(n=10/ group).A 1.5 cm longitudinal incision was made along the middle of the neck in pentobarbital-anesthetized rats.Pain threshold(PT) was measured using radiant heat.EA(1-2 mA

2 Hz/15 Hz) was applied to bilateral LI 18

ST 36-GB 34 for 30 min.The expression of SP

NK-1 R

COX-1

5-HT 1 AR and 5-HT 2 AR in the spinal cord(C 1-C 4) tissue were detected with immunohistochemistry.Results After the operation

the thermal PT was decreased obviously in comparison with normal control group(P<0.05).Compared with pre-operation

the PT of EA-Futu(LI 18) group increased markedly after treatment(P<0.05)

and no significant changes were found in PT in EA-ST 36-GB 34 group(P>0.05).The immunoactivity of SP

NK-1 R

COX-1 in the superficial dorsal horn in model group was increased significantly and that of 5-HT1 AR and 5-HT2 AR significantly and mildly

separately compared with control group(P<0.05).In comparison with model group

the immunoreactivity of SP

NK-1 R and COX-1 was decreased considerably

and that of 5-HT1 AR and 5-HT2 AR was upregulated remarkably in EA-LI 18 group(P<0.05).No significant changes were found in the immunoactivity of SP

NK-1 R

COX-1

5-HT1 AR and 5-HT2 AR in EA-ST 36-GB 34 group(P>0.05).Conclusion EA-Futu(LI 18) can significantly suppress pain reaction of neck incision in the rat

which is closely associated with its effects in downregulating the expression of SP

NK-1 R

COX-1 and upregulating that of 5-HT1 AR and 5-HT2 AR in the spinal dorsal horn.