Effects of resveratrol in the signaling of neuropathic pain involving P2X3 in the dorsal root ganglion of rats.

Neuropathic pain is a major public health problem because it has a considerable impact on life quality of patients. Neuropathic pain caused by a lesion or disease of the somatosensory nervous system, which causes unpleasant and abnormal sensation (dysesthesia), an increased response to painful stimuli (hyperalgesia), and pain in response to a stimulus that does not normally provoke pain (allodynia). P2X receptors from dorsal root ganglion (DRG) play a crucial role in facilitating pain transmission at peripheral and spinal sites. Resveratrol (Res) has neuroprotective effects and improves the pathological and behavioral outcomes of various types of nerve injury. The present study examined the effects of Res on neuropathic pain. Neuropathic pain animal model was created by partial sciatic nerve ligation (pSNL) surgery. We found that consecutive intraperitoneal administration of Res for 21 days reduced the mechanical and thermal nociceptive responses induced by pSNL in a dose-dependent manner. Moreover, Res administration reversed P2X3 expression and phosphorylation of ERK in DRG neurons after peripheral nerve injury. Our results suggested that Res may ameliorate neuropathic pain by suppressing P2X3 up-regulation and ERK phosphorylation in DRG of neuropathic pain rats. Therefore, we concluded that Res has a significant analgesic effect on alleviating neuropathic pain, and thus may serve as a therapeutic approach for neuropathic pain.