title: Postsynaptic glutamate transport at the climbing fiber-Purkinje cell synapse.
abstract: The role of postsynaptic, neuronal glutamate transporters in terminating signals at central excitatory synapses is not known. Stimulation of a climbing fiber input to cerebellar Purkinje cells was shown to generate an anionic current mediated by glutamate transporters. The kinetics of transporter currents were resolved by pulses of glutamate to outside-out membrane patches from Purkinje cells. Comparison of synaptic transporter currents to transporter currents expressed in Xenopus oocytes suggests that postsynaptic uptake at the climbing fiber synapse removes at least 22 percent of released glutamate. These neuronal transporter currents arise from synchronous activation of transporters that greatly outnumber activated AMPA receptors.
authors.affiliation: Vollum Institute, L-474, Oregon Health Sciences University, 3181 Southwest Sam Jackson Park Road, Portland, OR 97201, USA.
authors.forename: T S
authors.initials: TS
authors.lastname: Otis
authors.forename: M P
authors.initials: MP
authors.lastname: Kavanaugh
authors.forename: C E
authors.initials: CE
authors.lastname: Jahr
mesh_terms: D027322:Amino Acid Transport System X-AG; D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism*; D003998:Dicarboxylic Acids / Q000494:pharmacology; D050491:Glutamate Plasma Membrane Transport Proteins; D018698:Glutamic Acid / Q000378:metabolism*; D066298:In Vitro Techniques; D007700:Kinetics; D009412:Nerve Fibers / Q000378:metabolism*; D009865:Oocytes; D018408:Patch-Clamp Techniques; D011689:Purkinje Cells / Q000378:metabolism*; D011759:Pyrrolidines / Q000494:pharmacology; D051381:Rats; D018091:Receptors, AMPA / Q000378:metabolism; D017470:Receptors, Glutamate / Q000378:metabolism*; D027981:Symporters; D013569:Synapses / Q000378:metabolism*; D009435:Synaptic Transmission; D014981:Xenopus
chemical_list: D027322:Amino Acid Transport System X-AG; D002352:Carrier Proteins; D003998:Dicarboxylic Acids; D050491:Glutamate Plasma Membrane Transport Proteins; D011759:Pyrrolidines; D018091:Receptors, AMPA; D017470:Receptors, Glutamate; D027981:Symporters; C103758:pyrrolidine-2,3-dicarboxylic acid; C011274:3-hydroxyaspartic acid; D001224:Aspartic Acid; D018698:Glutamic Acid