Receptor for glutamate that functions as ligand-gated ion channel in the central nervous system and plays an important role in excitatory synaptic transmission. L-glutamate acts as an excitatory neurotransmitter at many synapses in the central nervous system. The postsynaptic actions of Glu are mediated by a variety of receptors that are named according to their selective agonists. This receptor binds domoate > kainate >> L-glutamate = quisqualate >> AMPA = NMDA. Homotetramer, and heterotetramer with either GRIK4 or GRIK5. Interacts with PRKCABP (By similarity). Interacts with NETO2 (By similarity). Partially edited. Belongs to the glutamate-gated ion channel (TC 1.A.10.1) family. GRIK3 subfamily.