title: Disrupting Glutamate Co-transmission Does Not Affect Acquisition of Conditioned Behavior Reinforced by Dopamine Neuron Activation.
abstract: Dopamine neurons in the ventral tegmental area (VTA) were previously found to express vesicular glutamate transporter 2 (VGLUT2) and to co-transmit glutamate in the ventral striatum (VStr). This capacity may play an important role in reinforcement learning. Although it is known that activation of the VTA-VStr dopamine system readily reinforces behavior, little is known about the role of glutamate co-transmission in such reinforcement. By combining electrode recording and optogenetics, we found that stimulation of VTA dopamine neurons in vivo evoked fast excitatory responses in many VStr neurons of adult mice. Whereas conditional knockout of the gene encoding VGLUT2 in dopamine neurons largely eliminated fast excitatory responses, it had little effect on the acquisition of conditioned responses reinforced by dopamine neuron activation. Therefore, glutamate co-transmission appears dispensable for acquisition of conditioned responding reinforced by DA neuron activation.
authors.affiliation: Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA.
authors.forename: Dong V
authors.initials: DV
authors.lastname: Wang
authors.affiliation: Department of Organismal Biology, Uppsala University, 752 36 Uppsala, Sweden.
authors.forename: Thomas
authors.initials: T
authors.lastname: Viereckel
authors.affiliation: Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA.
authors.forename: Vivien
authors.initials: V
authors.lastname: Zell
authors.affiliation: Department of Organismal Biology, Uppsala University, 752 36 Uppsala, Sweden.
authors.forename: Åsa
authors.initials: Å
authors.lastname: Konradsson-Geuken
authors.affiliation: Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA.
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Broker
authors.affiliation: Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA.
authors.forename: Aleksandr
authors.initials: A
authors.lastname: Talishinsky
authors.affiliation: Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA.
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Yoo
authors.affiliation: Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA.
authors.forename: Melissa H
authors.initials: MH
authors.lastname: Galinato
authors.affiliation: Department of Organismal Biology, Uppsala University, 752 36 Uppsala, Sweden.
authors.forename: Emma
authors.initials: E
authors.lastname: Arvidsson
authors.affiliation: Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Kesner
authors.affiliation: Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Hnasko
authors.affiliation: Department of Organismal Biology, Uppsala University, 752 36 Uppsala, Sweden.
authors.forename: Åsa
authors.initials: Å
authors.lastname: Wallén-Mackenzie
authors.affiliation: Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA. Electronic address: satoshi.ikemoto@nih.gov.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ikemoto
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D003213:Conditioning, Psychological; D059290:Dopaminergic Neurons / Q000378:metabolism*; D018698:Glutamic Acid / Q000378:metabolism*; D018345:Mice, Knockout; D017072:Neostriatum / Q000378:metabolism; D062308:Optogenetics; D017557:Ventral Tegmental Area / Q000378:metabolism; D050599:Vesicular Glutamate Transport Protein 2 / Q000378:metabolism
chemical_list: D050599:Vesicular Glutamate Transport Protein 2; D018698:Glutamic Acid
keywords: glutamate co-transmission; intracranial self-stimulation; mesolimbic dopamine system; nucleus accumbens; reinforcement learning; reward; ventral striatum