Objective To observe the effect of wrist-ankle acupuncture(WA) stimulation at "R_4"-"R_5"-"R_6" on the expression of glutamate(Glu) and phosphorylated protein NMDAR1(p-NMDAR1) of the spinal dorsal horn in spared nerve injury(SNI) rats

so as to explore its mechanism underlying improvement of SNI. Methods A total of 36 SD rats were randomly divi-ded into sham operation

model and WA groups

with 12 rats in each group. The SNI procedure comprised an axotomy and ligation of the tibial and common peroneal nerves leaving the sural nerve intact. Rats of the WA group were treated by acupuncture at "R_4"-"R_5"-"R_6" points from the 5

(th)

day to the 14(th) day to the 14

(th)

day after modeling. The mechanical pain thresholds were measured before and 5

10 and 14 d after SNI

respectively. The cold allodynia was dectected by Acetone solution dropped onto the lateral plantar surface of the paw. Glu content and p-NMDAR1 expression of spinal dorsal horn were detected by (th) day after modeling. The mechanical pain thresholds were measured before and 5

10 and 14 d after SNI

respectively. The cold allodynia was dectected by Acetone solution dropped onto the lateral plantar surface of the paw. Glu content and p-NMDAR1 expression of spinal dorsal horn were detected by

1

H-MRS

ELISA and immunohistochemistry methods. Results Compared with the sham operation group

the mechanical pain threshold of the model group was significantly decreased(P

<

0.01)

the duration of cold stimulation foot contraction was increased(P

<

0.01)

and the Glu content and p-NMDAR1 expression in the spinal dorsal horn were significantly increased(P

<

0.05

P

<

0.01). After WA intervention

the mechanical pain threshold was significantly increased(P

<

0.01)

the duration of cold stimulation was significantly shortened(P

<

0.01)

and Glu content and p-NMDAR1 protein expression of spinal dorsal horn were decreased significantly(P

<

0.05

P

<

0.01) in the WA group compared with the model group. Conclusion WA can reduce pain sensitivity in rats with neuropathic pain

possibly by inhibiting the expression of Glu and p-NMDAR1 in the spinal dorsal horn.