Glutamate receptor subunit AMPA (AMPAR)

The **glutamate receptor subunit AMPA** (commonly called the AMPA receptor or AMPAR) is a **tetrameric ligand-gated ion channel** found throughout the mammalian central nervous system. It is composed of combinations of four subunits (GluA1, GluA2, GluA3, GluA4, encoded by GRIA1–4) that assemble to create the core pore for ion flow. When the endogenous neurotransmitter glutamate binds to the receptor, it triggers the rapid opening of the channel, allowing mainly sodium (Na⁺) and, depending on subunit composition, calcium (Ca²⁺) ions to flow into the postsynaptic neuron, generating fast excitatory postsynaptic potentials. AMPA receptors are central to brain functions such as learning, memory, and synaptic plasticity. Their surface expression, trafficking, and functional properties are extensively regulated by auxiliary subunits and post-transcriptional modifications. Dysregulation of AMPA receptors is implicated in conditions such as epilepsy, stroke, and neurodegeneration. Several drugs, including antagonists for epilepsy and positive allosteric modulators for cognitive enhancement, target AMPA receptors due to their crucial role in synaptic transmission and neuronal excitability[1][2][3][4].

Other names

AMPA receptorα-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptorAMPA-type glutamate receptorIonotropic glutamate receptor AMPAGluA1–GluA4 (subunits)GRIA1–GRIA4 (genes)

Antagonists block ion conduction by inhibiting glutamate binding or channel opening - Positive allosteric modulators (AMPAkines) enhance receptor-mediated currents - Negative allosteric modulators reduce activity by decreasing channel opening or glutamate affinity