Kainate receptors in epilepsy

Abstract

Kainate receptors (KARs) belong to the glutamatergic receptor family and they are assembled from various combinations of GluK1-GluK5 subunits. In the central nervous system (CNS), these receptors are involved in fundamental neuronal operation-like synaptic transmission. Thus, excitatory postsynaptic events with a KAR-mediated component have been identified in different structures of the CNS including the hippocampus, amygdala, cerebellum, spinal cord, retina, and immature neocortex. A remarkable feature of KAR-mediated synaptic events is their small amplitude and slow kinetics. These receptors also play a major role in the control of neuronal excitability via the modulation of transmitter release at both excitatory and inhibitory connections, and through metabotropic signaling. More recently, it has been discovered that KARs are also key players in CNS pathology as in temporal lobe epilepsy. Indeed, in this pathology abnormal synaptic connections in dentate granule cells (DGCs) operate via KARs not present in naïve conditions. These aberrant KAR-operated synapses drastically alter the computational properties of DGCs. These latest discoveries open a promising and new vista for the development of novel antiepileptic strategies. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.