Microglia and intractable chronic pain.

Many pathological processes within the central nervous system are mediated by complex interactions between neurons and resident glial cells. In the case of painful peripheral neuropathy, spinal microglia react and undergo a series of changes that directly influence the establishment of neuropathic pain states. Purinergic signaling has been shown to be at the center of this reactivity, and here we review recent mechanistic advances describing the importance of microglial P2 receptors and their interactions with neuronal populations in the development of neuropathic pain.