Effects Of Electroacupuncture On The Cross-talk Between Spinal Cord Neuron And Microglia Cells In Model Rats With Neck Incision Pain

Object: In this study, we observed the effects of electroacupuncture（EA） on postoperative pain of thyroid gland in rats and the expression of ATP, ATP receptor, P2X7 R, FKN, Cat S and C X3CR1 in cervical spinal cord dorsal horn（the immune mechanism of the spinal cord in relieving pain after EA）, to provide experimental basis for clinical acupuncture anesthesia in thyroid surgery.Methods: 50 Wistar rats were divided into 5 groups, normal group, model group, Futu group, Hegu-Neiguan group, Zusanli- Yanglingquan group. We made a longitudinal incision in the neck of rats through, causing model of incisional pain and done electroacupuncture on bilateral Fu Tu acupoint, bilateral Hegu and Neiguan, Zusanli and Yanglingquan point（2/100 Hz, 30 min, 1m A）, observing and recording: 1 detecting pain threshold of rats in each group; 2 detecting the expression of ATP by high performance liquid phase technique; 3 detecting the expression of ATP receptor RNA by fluorescence quantitative RT-PCR method; 4 detecting the expression of P2X7R/FKN/CX3CR1 protein by Western-Blot method; 5 detecting the content of Cat S protein by ELISA.Result:1 There was no significant difference in the pain threshold of the rats among each group before the surgery. Comparing the model group with the normal group, rats’ thermal radiation pain threshold was significantly decreased（P<0.05）. Comparing the Futu group and Hegu-Neiguan group with the model group, rats’ thermal radiation pain threshold was significantly increased（P<0.05）, there was no differences between EA of Futu group and EA of Hegu Neiguan group. There was no significant difference between Zusanli- Yanglingquan group and normal group on rats’ heat radiation pain threshold.2 Compared with the normal group, the ATP of the cervical spinal dorsal horn（C3-C5） of the model group was significantly increased（P< 0.05）. Compared with the model group, the ATP content of the cervical spinal dorsal horn（C3-C5） of Futu group and Hegu-Neiguan group was significantly decreased（P<0.05）, there was no differences between EA of Futu group and EA of Hegu Neiguan group. There was no significant difference between Zusanli- Yanglingquan group and normal group on the ATP content of the cervical spinal dorsal horn（C3-C5）.3 Compared with the normal group, among the ATP receptors of rat carotid segment（C3-C5） in the spinal dorsal horn of model group, only P2X3 R,P2X4R,P2X7 R,P2Y12R receptor subtype gene m RNA relative expression increased significantly（P< 0.05）. 4 Compared with the normal group, the P2X7 R, s FKN, CX3CR1 of the cervical spinal dorsal horn（C3-C5） of the model group was significantly increased（P<0.05）, but the m FKN was significantly decreased（P<0.05）, at the same time the content of Cat S only got a upward trend. Compared with the model group, the P2X7 R, s FKN, CX3CR1 of the cervical spinal dorsal horn（C3-C5） of Futu group and Hegu-Neiguan group was significantly decreased（P< 0.05）, but the m FKN was significantly increased（P<0.05）, at the same time the content of Cat S only got a downward trend, there was no differences between EA of Futu group and EA of Hegu Neiguan group. There was no significant difference between Zusanli- Yanglingquan group and normal group on the P_2X7R, sFKN, CX3CR1, Cat S of the cervical spinal dorsal horn（C3-C5）.Conclusion:1 EA of Futu group and EA of Hegu Neiguan group got regulative effect on incision pain model with rats after thyroid surgery, there was no differences between EA of Futu group and EA of Hegu Neiguan group, but EA of Zusanli- Yanglingquan group did not get a significant effect.2 The regulating mechanism of EA of Futu group and EA of Hegu Neiguan group getting regulative effect on incision pain model with rats after thyroid surgery may be related to inhibiting the cross-talk between spinal cord neuron and microglia cel s（CX3CL1-CX3CR1） and inhibiting the inhibition the activities of ATP/P_2X7R/CatS/s FKN signaling pathway.