title: Effects of repeated yohimbine administration on reinstatement of palatable food seeking: involvement of dopamine D1-like receptors and food-associated cues.
abstract: Acute exposure to the pharmacological stressor yohimbine induces relapse to both food and drug seeking in a rat model. However, no systematic studies on the effects of chronic stress on relapse have been conducted. Because chronic stress causes changes in dopamine D1-like receptor-mediated transmission in prefrontal cortex (a relapse node), we tested the hypothesis that chronic exposure to stress increases vulnerability to relapse via dopamine-mediated mechanisms. Additionally, to determine the role of food-conditioned cues in reinstatement of food seeking, we made discrete food-paired cues either available (CS Present) or not available (CS Absent) during extinction and reinstatement testing. Rats responded for palatable food reinforcers in daily 3-hour sessions, and the behavior was extinguished. To model chronic stress, rats were injected daily with yohimbine (0.0, 2.5, or 5.0 mg/kg; i.p.) during the first 7 days of extinction. Injections were combined with SCH-23390 (0.0, 5.0, or 10.0 µg/kg; i.p.), a D1-like receptor antagonist. Rats were then tested for reinstatement of food seeking triggered by acute yohimbine (0.0, 1.0, or 2.0 mg/kg; i.p.) and pellet priming. Rats treated previously with chronic yohimbine displayed increased responding following acute yohimbine priming relative to non-chronically stressed rats, but in the CS Absent condition only. Conversely, the lower dose of chronic yohimbine caused an increase in pellet-primed reinstatement, but this effect was more pronounced in the CS Present condition. Importantly, SCH-23390 combined with repeated yohimbine injections attenuated these effects. Thus, chronic stress may increase vulnerability to relapse under specific circumstances via a dopamine D1-like receptor-mediated mechanism.
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA. kball@bloomu.edu.
authors.forename: Kevin T
authors.initials: KT
authors.lastname: Ball
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Leah
authors.initials: L
authors.lastname: Miller
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Sullivan
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Ashleigh
authors.initials: A
authors.lastname: Wells
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Olivia
authors.initials: O
authors.lastname: Best
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Brittany
authors.initials: B
authors.lastname: Cavanaugh
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Taylor
authors.initials: T
authors.lastname: Copus
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Nathan
authors.initials: N
authors.lastname: Corrigan
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Shaina
authors.initials: S
authors.lastname: Hawkins
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Krista
authors.initials: K
authors.lastname: Kobbe
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Ashley
authors.initials: A
authors.lastname: Schoener
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Johnathan
authors.initials: J
authors.lastname: Steiger
authors.affiliation: Department of Psychology, Bloomsburg University of Pennsylvania, Bloomsburg, PA, USA.
authors.forename: Lauren
authors.initials: L
authors.lastname: Vieweg
mesh_terms: D058669:Adrenergic alpha-2 Receptor Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D003216:Conditioning, Operant / Q000187:drug effects; D003463:Cues; D018492:Dopamine Antagonists / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005108:Extinction, Psychological / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects*; D005518:Food Preferences / Q000187:drug effects*; D008297:Male; D017207:Rats, Sprague-Dawley; D017447:Receptors, Dopamine D1 / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000502:physiology*; D015016:Yohimbine / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D058669:Adrenergic alpha-2 Receptor Antagonists; D001552:Benzazepines; D018492:Dopamine Antagonists; D017447:Receptors, Dopamine D1; C534628:SCH 23390; D015016:Yohimbine
keywords: Cue; dopamine; reinstatement; relapse; stress; yohimbine