Microglia in Neuropathic Pain

Neuropathic pain (NP) is pain resulting from lesions or disease of the somatosensory system. A cardinal feature of NP is tactile allodynia (a painful response to normally innocuous stimulation). In 2003, a breakthrough strategy for inducing NP was proposed in which microglia of the spinal dorsal horn (SDH) are activated after peripheral nerve injury (PNI) to overexpress P2X4 receptor (P2X4R) and play an important role in inducing tactile allodynia. In 2005, it was reported that stimulation of microglial P2X4Rs evokes the release of brain-derived neurotrophic factor (BDNF), which causes a depolarizing shift of the anion reversal potential (E