title: Chronic cocaine reduces RGS4 mRNA in rat prefrontal cortex and dorsal striatum.
abstract: Neuroadaptations affecting dopamine transmission within the prefrontal cortex and striatum are thought to underlie relapse to cocaine seeking after extended periods of abstinence. Regulator of G-protein signaling 4 (RGS4) is a forebrain-enriched protein known to be dynamically regulated by dopamine receptors in response to acute psychostimulant administration. In this report, chronic noncontingent (cocaine binge) or response-contingent (self-administration) delivery of cocaine followed by 2-3 weeks of abstinence resulted in a decrease of RGS4 mRNA in the dorsal striatum and prefrontal cortex. Furthermore, re-exposure to the cocaine-associated context after abstinence renewed the drug seeking and restored the levels of RGS4 mRNA to control values. Changes in RGS4 mRNA levels might signal abnormal receptor G-protein coupling that impacts cocaine seeking.
authors.affiliation: Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina 29425, USA.
authors.forename: Marek
authors.initials: M
authors.lastname: Schwendt
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Hearing
authors.forename: Ronald E
authors.initials: RE
authors.lastname: See
authors.forename: Jacqueline F
authors.initials: JF
authors.lastname: McGinty
mesh_terms: D000818:Animals; D016739:Behavior, Addictive / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology; D003042:Cocaine / Q000494:pharmacology*; D019970:Cocaine-Related Disorders / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology; D004195:Disease Models, Animal; D004298:Dopamine / Q000378:metabolism; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology; D015536:Down-Regulation / Q000187:drug effects / Q000502:physiology; D004334:Drug Administration Schedule; D008297:Male; D017072:Neostriatum / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D017397:Prefrontal Cortex / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D020710:RGS Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011954:Receptors, Dopamine / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000187:drug effects / Q000378:metabolism; D012008:Recurrence; D012646:Self Administration; D013375:Substance Withdrawal Syndrome / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology
chemical_list: D018765:Dopamine Uptake Inhibitors; D020710:RGS Proteins; D012333:RNA, Messenger; D011954:Receptors, Dopamine; D043562:Receptors, G-Protein-Coupled; C098799:RGS4 protein; D003042:Cocaine; D004298:Dopamine