title: Photochemically knocking out glutamate receptors in vivo.
abstract: AMPA (alpha-amino-3-hydroxy-5-methyl-4-isooxazole) receptors, a major subtype of ionotropic glutamate receptors (iGluRs), mediate the majority of the fast communication between neurons, and the activity-dependent trafficking of AMPA receptors at synapses plays a role in mammalian learning and memory. Here we describe the design, synthesis, and evaluation of a photoreactive AMPA receptor antagonist that provides a means of "knocking out" AMPA receptors present on the surface of cells. The antagonist, 6-azido-7-nitro-1,4-dihydroquinoxaline-2,3-dione (ANQX), was designed by introducing a photoreactive azido group onto a quinoxalinedione inhibitor scaffold. Computational docking of ANQX to the AMPA receptor ligand-binding core predicted efficient binding to AMPA receptors. Glutamate-evoked currents were reversibly blocked at micromolar ANQX concentrations prior to photolysis and irreversibly blocked following photolysis. ANQX provides a means of directly evaluating the trafficking of native AMPA receptors with unparalleled spatiotemporal resolution.
authors.affiliation: Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94143-2280, USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: Chambers
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Gouda
authors.forename: David M
authors.initials: DM
authors.lastname: Young
authors.forename: Irwin D
authors.initials: ID
authors.lastname: Kuntz
authors.forename: Pamela M
authors.initials: PM
authors.lastname: England
mesh_terms: D000818:Animals; D018691:Excitatory Amino Acid Antagonists / Q000737:chemistry / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism; D009574:Nitro Compounds / Q000737:chemistry / Q000494:pharmacology; D010777:Photochemistry; D011804:Quinolines / Q000737:chemistry / Q000494:pharmacology; D011810:Quinoxalines / Q000737:chemistry / Q000494:pharmacology; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism* / Q000528:radiation effects*; D013569:Synapses / Q000378:metabolism*; D014466:Ultraviolet Rays; D014981:Xenopus
chemical_list: C493868:6-azido-7-nitro-1,4-dihydroquinoxaline-2,3-dione; D018691:Excitatory Amino Acid Antagonists; D009574:Nitro Compounds; D011804:Quinolines; D011810:Quinoxalines; D018091:Receptors, AMPA; C056723:FG 9041