title: Comparison of nafadotride, CNQX, and haloperidol on acquisition versus expression of amphetamine-conditioned place preference in rats.
abstract: Neurotransmission at dopamine (DA) and glutamate synapses has been implicated in conditioning place preference (CPP) in rats, but different receptor subtypes may be differentially involved in acquisition and expression. A balanced CPP was used to study the role of DA D2 and D3 and glutamatergic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate receptors in acquisition and expression of amphetamine (2.0 mg/kg) CPP. We tested the DA D3 receptor-preferring antagonist nafadotride, the AMPA/kainate glutamate-receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione disodium salt (CNQX), and the DA D2 receptor-preferring antagonist haloperidol. The results revealed that nafadotride (0.5 mg/kg) and CNQX (0.05 mg/kg) blocked the expression of amphetamine CPP at a dose that failed to block acquisition. In contrast, haloperidol (0.1 mg/kg) blocked the acquisition of CPP at a dose that failed to block expression. Cotreatment with subthreshold doses of nafadotride (0.1 mg/kg) and CNQX (0.01 mg/kg) before the test session failed to block the expression of CPP. The results suggest that AMPA/kainate and DA D3 receptors are more strongly involved in the expression of amphetamine CPP and D2 receptors are more strongly involved in the acquisition of amphetamine CPP.
authors.affiliation: Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada.
authors.forename: Tomek J
authors.initials: TJ
authors.lastname: Banasikowski
authors.forename: Lindsey S
authors.initials: LS
authors.lastname: MacLeod
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Beninger
mesh_terms: D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology*; D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D003213:Conditioning, Psychological / Q000187:drug effects*; D006220:Haloperidol / Q000494:pharmacology*; D008297:Male; D009281:Naphthalenes / Q000494:pharmacology*; D011759:Pyrrolidines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000502:physiology; D017448:Receptors, Dopamine D2 / Q000502:physiology; D050637:Receptors, Dopamine D3 / Q000502:physiology
chemical_list: D009281:Naphthalenes; D011759:Pyrrolidines; D018091:Receptors, AMPA; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D000661:Amphetamine; D006220:Haloperidol; C097285:nafadotride