Glutamate ionotropic receptor AMPA type subunit (AMPA receptor subunit (commonly abbreviated as GluA1, GluA2, GluA3, or GluA4 depending on the gene; e.g., GRIA1–GRIA4))

Glutamate ionotropic receptor AMPA type subunits are integral membrane proteins that assemble into tetrameric complexes known as **AMPA receptors**. These ligand-gated ion channels mediate fast excitatory synaptic transmission in the central nervous system by permitting sodium influx upon binding glutamate. Each functional AMPA receptor consists of four core subunits—GluA1 through GluA4—encoded by GRIA1–GRIA4 genes. The structure includes extracellular domains responsible for ligand binding and a transmembrane domain forming an ion-conducting pore. These receptors play a critical role in synaptic plasticity underlying learning and memory but also contribute to pathological processes such as excitotoxicity during stroke or epilepsy when overactivated.[8][6][1] They are important drug targets but present therapeutic challenges due to their ubiquitous role in CNS physiology.[2]

Other names

AMPA receptor subunitα-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor subunitGluA1 (GRIA1), GluA2 (GRIA2), GluA3 (GRIA3), GluA4 (GRIA4)Sometimes referred to as "GluR" followed by subtype number

Drugs targeting this molecule act via several mechanisms including: - Competitive antagonism at the glutamate binding site - Noncompetitive antagonism at allosteric sites within the transmembrane domain or elsewhere on the protein complex - Positive allosteric modulation to enhance channel opening or reduce desensitization