Localization of kainate receptors in inner and outer hair cell synapses

Drawing illustrates the distribution of kainate receptor subunits, GluK1,2,4,5, and the AMPA receptor subunit, GluA2, at synapses on inner (IHC) and outer (OHC) hair cells in the adult rat, as described in this study. At IHC afferent (a) synapses, GluA2, GluK2 and GluK5 are postsynaptic and GluK2 is presynaptic. OHC afferent synapses bearing ribbons (usually one or two; colored green in drawing) have GluK2 and GluK5, while those lacking ribbons have small amounts of GluK5 only; efferent (e) synapses have GluK1, GluK2, and GluK5. 265