Nicotine enhancement and reinforcer devaluation: Interaction with opioid receptors
Autor: | Jesse A. Suhaka, Jessie L. Phillips, Ari P. Kirshenbaum, Maiary Voltolini de Souza Pinto |
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Rok vydání: | 2016 |
Předmět: |
Nicotine
medicine.medical_treatment Clinical Biochemistry (+)-Naloxone Pharmacology Toxicology Biochemistry Rats Sprague-Dawley 03 medical and health sciences Behavioral Neuroscience 0302 clinical medicine medicine Animals Dosing Receptor Reinforcement Saline Biological Psychiatry Naloxone business.industry Naltrexone Rats 030227 psychiatry Discontinuation Opioid Receptors Opioid business Reinforcement Psychology 030217 neurology & neurosurgery medicine.drug |
Zdroj: | Pharmacology Biochemistry and Behavior. :1-7 |
ISSN: | 0091-3057 |
Popis: | In rats, nicotine enhances responding maintained by non-pharmacological reinforcers, and discontinuation of nicotine devalues those same reinforcers. The goal of this study was to assess the interaction of nicotine and opioid receptors and to evaluate the degree to which nicotine enhancement and nicotine-induced devaluation are related to opioid activation. Nicotine (0.4 mg/kg), or nicotine plus naloxone (0.3 or 3.0 mg/kg), was delivered to rats prior to progressive ratio (PR) schedule sessions in which sucrose was used as a reinforcer. PR-schedule responding was assessed during ten daily sessions of drug delivery, and for three post-dosing days/sessions. Control groups for this investigation included a saline-only condition, and naloxone-only (0.3 or 3.0 mg/kg) conditions. When administered in conjunction with nicotine, both naloxone doses attenuated nicotine enhancement of the sucrose reinforcer, and the combination of the larger dose of naloxone (3.0 mg/kg) with nicotine produced significant impairments in sucrose reinforced responding. When administered alone, neither dose of naloxone (0.3 & 3.0 mg/kg) significantly altered responding in comparison to saline. Furthermore, when dosing was discontinued after ten once-daily doses, all nicotine groups (nicotine-only and nicotine + naloxone combination) demonstrated significant decreases in sucrose reinforcement compared to the saline group. Although opioid antagonism attenuated reinforcement enhancement by nicotine, it did not prevent reinforcer devaluation upon discontinuation of nicotine dosing, and the higher dose of naloxone (3.0 mg/kg) produced decrements upon discontinuation on its own in the absence of nicotine. |
Databáze: | OpenAIRE |
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