Kainate receptors and pain: from dorsal root ganglion to the anterior cingulate cortex.

Ionotropic glutamate receptors contain three subtypes: NMDA, AMPA and kainate receptors. The former two receptor subtypes have well defined roles in nociception, while the role of kainate receptors in pain is not as well characterized. Kainate receptors are expressed in nociceptive pathways, including the dorsal root ganglion, spinal cord, thalamus and cortex. Electrophysiological studies show that functional kainate receptors are located postsynaptically, where they mediate a portion of excitatory synaptic transmission, or are located presynaptically, where they modulate excitatory or inhibitory neurotransmission. Recent genetic and pharmacological studies suggest that kainate receptors can regulate nociceptive responses. These results highlight kainate receptors as a target for the development of new treatments for chronic pain.