Study On The Analgesic Mechanism Of Electroacupuncture At Ningjiaji Acupoint On Neuropathic Pain Model Rats With Cervical Radiculopathy

Objective: To investigate the effect of electroacupuncture at Jingjiaji on the neuropathic pain model of CSR,and to observe the functional state of injured neurons and the expression of the key elements of neuron glia chemokine network signal system in the dorsal horn of spinal cord,so as to find out the relationship and explore the analgesic mechanism of electro-acupuncture,so as to provide reference for the treatment of cervical spondylotic radiculopathy by Electro-acupuncture at Jingjiaji Experimental basis.Methods: In the first part,the neuropathic pain model of cervical spondylotic radiculopathy was established by ligating the cervical nerve root of Sprague-Dawley(SD)rats.After the establishment of the model,the general behavior,pain induced by thermal and mechanical stimulation and evoked potential were detected to verify the success of the model.In the second part,the cervical nerve root was added with intrathecal tube on the basis of the first part.In the first part,48 rats were divided into four groups: blank group,model group,sham operation group and electroacupuncture group.Two weeks after operation,the rats in electroacupuncture group were intervened by electroacupuncture at Jingjiaji point under binding,while the rats in model group and sham operation group were equally tied.The threshold of heat pain and the contents of glutamic acid,prostaglandin and no in each group were observed and recorded VGCC expression.The second part was divided into blank group,model group,sham operation group,electroacupuncture group,LAA astrocyte inhibitor group(LAA group)and LAA+electroacupuncture group-?-CD11b/Cr3,GFAP,CX3CR1 receptor,CCR2 receptor,TLR4,p38-MAPK,and NF were detected by immunofluorescence-?The expression of IL-1 in C6 and C7 spinal dorsal horn was detected by immunohistochemistry,IL-6,IL-18,TNF-? RT-PCR and Western blot were used to detect the levels of excitatory amino acids,inflammatory factors and the expressions of NMDA and AMPA in thalamus and cerebral cortex.Results: In the first part,EA group could effectively relieve the pain of CSR model rats,and the contents of glutamate,prostaglandin and no in neurons of EA group were significantly improved compared with those of model group(P<0.05).The expressions of CGRP receptor,AC and VGCC in spinal dorsal horn were significantly decreased(P<0.05).In the second part,EA at Jiaji and intrathecal injection of LAA astrocyte inhibitor could effectively reduce the pain,CX3CR1 receptor,CCR2 receptor and TLR4 production,GFAP and CD11b/Cr3 expression(P<0.05),and inhibit all kinds of neuroinflammatory mediators IL-1?,IL-18,IL-6,TNF-?.The expression of NMDA and AMPA in spinal dorsal horn was significantly decreased(P<0.05).The effect of LAA group was better than that of EA group(P<0.05).Conclusion:1.The results of the first part and the second part show that electroacupuncture at Cervical Jiaji can improve the neuropathic pain model of cervical spondylotic radiculo Pathy in rats.2.EA at Jingjiaji can inhibit the expression of CGRP receptor and AC,and reduce the contents of glutamate,prostaglandin and NO.3.EA at Jingjiaji can inhibit the synthesis and secretion of inflammatory mediators IL-1?,IL-18,IL-6 and TNF-?,and can effectively reduce the expression of NMDA and AMPA in spinal dorsal horn.4.The regulatory mechanism of electroacupuncture at Jingjiaji point on the neuropathic pain model of cervical s Pondylotic radiculopathy may be related to the inhibition of cx3cl1-cx3cr1 communication and p38-MAPK signaling pathway between neurons and glial cells in cervical spinal cord.