Receptor for activated C kinase 1 mediates the chronic constriction injury-induced neuropathic pain in the rats' peripheral and central nervous system.

Peripheral and central sensitization has been reported as significant features in the course of the occurrence and development of neuropathic pain (NP). Receptor for activated C kinase 1 (RACK1), a scaffold protein, participated in fundamental cellular activities and various neuronal functions. Peripheral and central sensitization are a state that the morphology of neuronal cell bodies as well as the corresponding function change, whether this process can be regulated by RACK1 is still unknown. In this study, the biological effects and mechanisms of RACK1 contributes to the pathogenesis of chronic constriction injury (CCI)-induced neuropathic pain were investigated. By western blot and staining, we found that RACK1 protein changed in dorsal root ganglion (DRG) neurons and spinal cord (SC) neurons except glial cells after CCI. Especially, RACK1 was co-located with IB4-, CGRP-positive neurons, suggesting it was related to integrate nociceptive information from the primary aff ;erents in DRG. The successful establishment of CCI models also directly led to mechanical allodynia and heat hyperalgesia, which could be reversed by intrathecal injection of RACK1 siRNA. Furthermore, intrathecal injection of RACK1 siRNA reduced the expression of RACK1 and accompanying spinal c-fos, which is the transcription factor and marker of neuronal activation. These results suggested that targeting RACK1 be a sensible approach for treating NP.