title: The paraventricular nucleus of the thalamus is differentially recruited by stimuli conditioned to the availability of cocaine versus palatable food.
abstract: The paraventricular nucleus of the thalamus (PVT) is not traditionally considered part of the brain addiction neurocircuitry but has received growing attention with regard to a role in the modulation of drug-seeking behavior. This study sought to establish the pattern of neural activation induced by a response-reinstating discriminative stimulus (SD) conditioned to either cocaine (COC) or a conventional reinforcer using a palatable food substance, sweetened condensed milk (SCM). Male Wistar rats were trained to associate one SD(S+; COC or SCM availability) and a distinctly different SD(S-; non-reward; i.e. the availability of saline or the absence of SCM). Following extinction of COC- and SCM-reinforced responding, rats were presented with the respective S+or S-alone and tested for the reinstatement of reward seeking. The COC S+and SCM S+elicited identical reinstatement, whereas the non-reward S-was behaviorally ineffective. PVT sections were obtained following completion of the reinstatement tests and labeled for Fos. The number of Fos+neurons was compared among rats that were presented with the COC S+, SCM S+or S-. Rats that were presented with the COC S+exhibited a significant increase in Fos expression compared with rats that were presented with the S-. Moreover, Fos expression was significantly correlated with the number of reinstatement responses that were induced by the COC S+. In contrast, the SCM S+and S-produced identical increases in Fos expression, without behaviorally relevant correlations. The findings implicate the PVT as an important site that is selectively recruited during COC-seeking behavior.
authors.affiliation: Molecular and Cellular Neuroscience Department, The Scripps Research Institute, La Jolla, CA, USA.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Matzeu
authors.affiliation: Molecular and Cellular Neuroscience Department, The Scripps Research Institute, La Jolla, CA, USA.
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Cauvi
authors.affiliation: Molecular and Cellular Neuroscience Department, The Scripps Research Institute, La Jolla, CA, USA.
authors.forename: Tony M
authors.initials: TM
authors.lastname: Kerr
authors.affiliation: Molecular and Cellular Neuroscience Department, The Scripps Research Institute, La Jolla, CA, USA.
authors.forename: Friedbert
authors.initials: F
authors.lastname: Weiss
authors.affiliation: Molecular and Cellular Neuroscience Department, The Scripps Research Institute, La Jolla, CA, USA.
authors.forename: Rémi
authors.initials: R
authors.lastname: Martin-Fardon
mesh_terms: D000821:Animal Feed; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D003042:Cocaine / Q000494:pharmacology*; D003216:Conditioning, Operant / Q000187:drug effects*; D003463:Cues; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology; D058999:Drug-Seeking Behavior / Q000187:drug effects*; D008297:Male; D023421:Models, Animal; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D012646:Self Administration; D013788:Thalamus / Q000187:drug effects
chemical_list: D018765:Dopamine Uptake Inhibitors; D003042:Cocaine
keywords: Cocaine; discriminative stimulus; reinstatement