title: Activation of a Temporal Memory in Purkinje Cells by the mGluR7 Receptor.
abstract: Cerebellar Purkinje cells can learn to respond to a conditioned stimulus with an adaptively timed pause in firing. This response was usually ascribed to long-term depression of parallel fiber to Purkinje cell synapses but has recently been shown to be due to a previously unknown form of learning involving an intrinsic cellular timing mechanism. Here, we investigate how these responses are elicited. They are resistant to blockade of GABAergic inhibition, suggesting that they are caused by glutamate release rather than by a changed balance between GABA and glutamate. We show that the responses are abolished by antagonists of the mGlu7 receptor but not significantly affected by other glutamate antagonists. These results support the existence of a distinct learning mechanism, different from changes in synaptic strength. They also demonstrate in vivo post-synaptic inhibition mediated by glutamate and show that the mGlu7 receptor is involved in activating intrinsic temporal memory.
authors.affiliation: Associative Learning Group, Department of Experimental Medical Science, Lund University, 22184 Lund, Sweden; The Linnaeus Center Thinking in Time: Cognition, Communication & Learning, Lund University, 22184 Lund, Sweden. Electronic address: fredrik.johansson@med.lu.se.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Johansson
authors.affiliation: Associative Learning Group, Department of Experimental Medical Science, Lund University, 22184 Lund, Sweden.
authors.forename: Hannes A E
authors.initials: HA
authors.lastname: Carlsson
authors.affiliation: Associative Learning Group, Department of Experimental Medical Science, Lund University, 22184 Lund, Sweden; The Linnaeus Center Thinking in Time: Cognition, Communication & Learning, Lund University, 22184 Lund, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Rasmussen
authors.affiliation: Department of Neuroscience, Physiology & Pharmacology, University College London, London WC1E 6BT, UK.
authors.forename: Christopher H
authors.initials: CH
authors.lastname: Yeo
authors.affiliation: Associative Learning Group, Department of Experimental Medical Science, Lund University, 22184 Lund, Sweden; The Linnaeus Center Thinking in Time: Cognition, Communication & Learning, Lund University, 22184 Lund, Sweden.
authors.forename: Germund
authors.initials: G
authors.lastname: Hesslow
mesh_terms: D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D004558:Electric Stimulation; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005289:Ferrets; D018698:Glutamic Acid / Q000378:metabolism; D008297:Male; D018408:Patch-Clamp Techniques; D011689:Purkinje Cells / Q000187:drug effects / Q000378:metabolism*; D011728:Pyridones / Q000494:pharmacology; D011810:Quinoxalines / Q000494:pharmacology; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors / Q000378:metabolism; D018094:Receptors, Metabotropic Glutamate / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014966:Xanthenes / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: C553164:6-(4-methoxyphenyl)-5-methyl-3-pyridin-4-ylisoxazonolo(4,5-c)pyridin-4(5H)-one; D000596:Amino Acids; D018691:Excitatory Amino Acid Antagonists; C114624:LY 341495; D011728:Pyridones; D011810:Quinoxalines; D018091:Receptors, AMPA; D018094:Receptors, Metabotropic Glutamate; D014966:Xanthenes; C102719:metabotropic glutamate receptor 7; C062865:2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid
keywords: Purkinje cell; cerebellum; classical conditioning; glutamate; mGluR1; mGluR7; temporal; timing