title: Nucleus accumbens AMPA receptor involvement in cocaine-conditioned place preference under different dietary conditions in rats.
abstract: BACKGROUND
  When ad libitum-fed (AL) rats undergo cocaine place preference conditioning (CPP) but are switched to food restriction (FR) for testing, CPP is enhanced and preference scores correlate with phosphorylation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor GluA1 at Ser845 in nucleus accumbens (NAc) core.
  
  
  OBJECTIVE
  The present study tested whether a similar association exists in AL rats and whether an inhibitor of Ca(2+)-permeable AMPARs blocks CPP expression in either diet group.
  
  
  METHODS
  In experiments 1-3, AL rats were conditioned with cocaine (12.0 mg/kg, i.p.). Three weeks later, CPP was tested daily and brains were harvested after the fifth test. Western analyses were used to probe for levels of AMPA receptors in NAc. In experiment 4, AL rats were conditioned, half were switched to FR for testing, and half in each diet group received NAc core microinjection of 1-naphthylacetyl spermine (NASPM (NASPM) (25.0 μg) prior to each test.
  
  
  RESULTS
  In experiment 1, CPP expression in AL rats was associated with elevated pSer845-GluA1, GluA1, and GluA2 in NAc. In experiment 2, the correlation between pSer845-GluA1 and CPP was localized to NAc core. In experiment 3, pSer845-GluA1 following a CPP test was higher in NAc synaptic membranes of FR relative to AL rats. In experiment 4, NASPM blocked CPP expression in both diet groups.
  
  
  CONCLUSIONS
  Results support a scheme in which pSer845-GluA1 in NAc core underlies expression of cocaine CPP and does so by stabilizing or trafficking Ca(2+)-permeable AMPARs to the synaptic membrane. The more robust CPP of FR rats may result from upregulation of stimulus-induced pSer845-GluA1.
authors.affiliation: Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, Alexandria Center for Life Sciences, 450 East 29th Street, New York, NY, 10016, USA.
authors.forename: Danielle
authors.initials: D
authors.lastname: Zheng
authors.affiliation: Department of Psychiatry, New York University School of Medicine, Alexandria Center for Life Sciences, 450 East 29th Street, New York, NY, 10016, USA.
authors.forename: Soledad
authors.initials: S
authors.lastname: Cabeza de Vaca
authors.affiliation: Department of Psychiatry, New York University School of Medicine, Alexandria Center for Life Sciences, 450 East 29th Street, New York, NY, 10016, USA.
authors.forename: Zachary
authors.initials: Z
authors.lastname: Jurkowski
authors.affiliation: Department of Psychiatry, New York University School of Medicine, Alexandria Center for Life Sciences, 450 East 29th Street, New York, NY, 10016, USA. kc16@nyu.edu.|Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, Alexandria Center for Life Sciences, 450 East 29th Street, New York, NY, 10016, USA. kc16@nyu.edu.
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Carr
mesh_terms: D000818:Animals; D031204:Caloric Restriction / Q000379:methods; D003042:Cocaine / Q000494:pharmacology*; D003213:Conditioning, Psychological / Q000187:drug effects* / Q000502:physiology; D005247:Feeding Behavior / Q000187:drug effects / Q000502:physiology / Q000523:psychology; D008297:Male; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000378:metabolism*
chemical_list: D018091:Receptors, AMPA; D003042:Cocaine
keywords: Cocaine; Conditioned place preference; Food restriction; GluA1; Nucleus accumbens