title: Food restriction induces synaptic incorporation of calcium-permeable AMPA receptors in nucleus accumbens.
abstract: Chronic food restriction potentiates behavioral and cellular responses to drugs of abuse and D-1 dopamine receptor agonists administered systemically or locally in the nucleus accumbens (NAc). However, the alterations in NAc synaptic transmission underlying these effects are incompletely understood. AMPA receptor trafficking is a major mechanism for regulating synaptic strength, and previous studies have shown that both sucrose and d-amphetamine rapidly alter the abundance of AMPA receptor subunits in the NAc postsynaptic density (PSD) in a manner that differs between food-restricted and ad libitum fed rats. In this study we examined whether food restriction, in the absence of reward stimulus challenge, alters AMPAR subunit abundance in the NAc PSD. Food restriction was found to increase surface expression and, specifically, PSD abundance, of GluA1 but not GluA2, suggesting synaptic incorporation of GluA2-lacking Ca2+-permeable AMPARs (CP-AMPARs). Naspm, an antagonist of CP-AMPARs, decreased the amplitude of evoked EPSCs in NAc shell, and blocked the enhanced locomotor response to local microinjection of the D-1 receptor agonist, SKF-82958, in food-restricted, but not ad libitum fed, subjects. Although microinjection of the D-2 receptor agonist, quinpirole, also induced greater locomotor activation in food-restricted than ad libitum fed rats, this effect was not decreased by Naspm. Taken together, the present findings are consistent with the synaptic incorporation of CP-AMPARs in D-1 receptor-expressing medium spiny neurons in NAc as a mechanistic underpinning of the enhanced responsiveness of food-restricted rats to natural rewards and drugs of abuse.
authors.affiliation: Department of Psychiatry, New York University School of Medicine, New York, NY, USA.
authors.forename: Jiangyong
authors.initials: J
authors.lastname: Ouyang
authors.affiliation: Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY, USA.|Department of Otolaryngology, New York University School of Medicine, New York, NY, USA.|Department of Neuroscience/Physiology, New York University School of Medicine, New York, NY, USA.
authors.forename: Ioana
authors.initials: I
authors.lastname: Carcea
authors.affiliation: Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY, USA.|Department of Otolaryngology, New York University School of Medicine, New York, NY, USA.|Department of Neuroscience/Physiology, New York University School of Medicine, New York, NY, USA.
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Schiavo
authors.affiliation: Department of Psychiatry, New York University School of Medicine, New York, NY, USA.
authors.forename: Kymry T
authors.initials: KT
authors.lastname: Jones
authors.affiliation: Department of Psychiatry, New York University School of Medicine, New York, NY, USA.
authors.forename: Ariana
authors.initials: A
authors.lastname: Rabinowitsch
authors.affiliation: Department of Psychiatry, New York University School of Medicine, New York, NY, USA.
authors.forename: Rhonda
authors.initials: R
authors.lastname: Kolaric
authors.affiliation: Department of Psychiatry, New York University School of Medicine, New York, NY, USA.
authors.forename: Soledad
authors.initials: S
authors.lastname: Cabeza de Vaca
authors.affiliation: Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY, USA.|Department of Otolaryngology, New York University School of Medicine, New York, NY, USA.|Department of Neuroscience/Physiology, New York University School of Medicine, New York, NY, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Froemke
authors.affiliation: Department of Psychiatry, New York University School of Medicine, New York, NY, USA.|Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, USA.|Alexandria Center for Life Sciences, 450 East 29th Street, New York, NY, 10016, USA.
authors.forename: Kenneth D
authors.identifier: 0000-0001-6567-6376
authors.initials: KD
authors.lastname: Carr
mesh_terms: D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D031204:Caloric Restriction; D018492:Dopamine Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials; D008297:Male; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D057907:Post-Synaptic Density / Q000378:metabolism* / Q000502:physiology; D019257:Quinpirole / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000235:genetics / Q000378:metabolism*; D017447:Receptors, Dopamine D1 / Q000235:genetics / Q000378:metabolism
chemical_list: D001552:Benzazepines; D002118:Calcium; D018492:Dopamine Antagonists; D019257:Quinpirole; D018091:Receptors, AMPA; D017447:Receptors, Dopamine D1; C071262:SK&F 82958; C104722:glutamate receptor ionotropic, AMPA 2
keywords: addiction; dieting; neuroplasticity; reward