AMPA receptor (GluA2) - "Activation, potentiation and inhibition of AMPA receptors on the Patchliner"
Patchliner application note (1.2 MB)
AMPA receptors are cation-permeable ionotropic glutamate receptors of the non-NMDA receptor subfamily. To date four subunits, GluA1-4, have been identified which are of similar size (approx. 900 kDa) and share 68-73% amino acid sequence identity. The human GluA2 subunit is encoded by the GRIA2 gene located on the 4q32-33 chromosome. Each of the 4 subunits has four distinct domains: an extracellular amino acid terminal domain (ATD); the extracellular ligand binding domain (LBD); the transmembrane domain (TMD) with 3 transmembrane segments (M1, M3 and M4) and 1 cytoplasmic facing re-entrant loop (M2); and an intracellular carboxyterminal domain. The functional receptor exists as a tetramer, either as homomers or heteromers (GluA1 and GluA4). The vast majority of excitatory fast synaptic transmission in the mammalian central nervous system is mediated by AMPA receptors of differing subunit combinations. It is well known that glutamate is a neurotoxin and it is proposed that overactivation of ionotropic glutamate receptors may underlie many neurodegenerative disorders such as ischemic stroke, epilepsy, Parkinson’s and dementia, amongst others. Enhancement of AMPA receptor activation by, for example, BDNF, has been proposed to have beneficial effects on learning and memory and has potential therapeutic value in the treatment of depression, Huntington’s and Parkinson’s diseases. Here we present data collected on an 8-channel Patchliner showing recordings of GluA2-mediated currents. Glutamate activated GluA2 receptors with an EC50 similar to those reported in the literature. CNQX inhibited and LY404187 enhanced GluA2-mediated responses.