Glutamatergic synapse pathway

Glutamatergic Synapse Pathway Glutamate is the major excitatory neurotransmitter at almost all synapses in the vertebrate central nervous system (CNS). Glutamate is packaged into synaptic vesicles in the glutamatergic presynaptic terminals, and released into the synaptic cleft through the fusion of synaptic vesicles to the membrane at the active zone.

Once released, glutamate acts on postsynaptic glutamate receptors to regulate several neuronal functions, such as neuronal migration, excitability, plasticity, long-term potentiation (LTP) and long-term depression (LTD). Glutamate receptors are transmembrane proteins, they are numerous and highly complex and can be divided into two main categories: voltage-sensitive ionotropic glutamate receptors (iGluRs), which are glutamate-gated ion channels, and ligand-sensitive metabotropic glutamate receptors (mGluRs), which are glutamate-activated G protein-coupled receptors (GPCRs).

Acting as cation channels that open upon glutamate binding, postsynaptic iGluRs mediate the fast excitatory transmission.

IGluRs can be further categorized into N-methyl-d-aspartate (NMDA) receptors, Îą-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors and Kainate (KA) receptors. AMPA receptors are the first target of glutamate released from presynaptic terminals, leading to post-synaptic membrane depolarization through the influx of sodium, and therefore play a fundamental role in synapse maturation and plasticity. In addition, AMPA receptors can be regulated by auxiliary proteins that participate in trafficking, such as TAPC1. AMPA receptors are heterotetramers formed by tow dimers with different combinations of the four AMPARs subunits GluA1-4, and usually GluA1/GluA2 and GluA2/GluA3 in mammalian CNS. Find more: https://www.creative-diagnostics.com/glutamatergic-synapse-pathway.htm