title: Effects of varenicline on operant self-administration of alcohol and/or nicotine in a rat model of co-abuse.
abstract: Alcohol and nicotine (in the form of tobacco) are often taken together, with increased negative health consequences. Co-use may modify intake of one or both of the drugs, or the effects of drugs used to treat nicotine or alcohol addiction. Varenicline is commonly prescribed as an aid to enhance quitting smoking. More recently it has been shown to reduce alcohol intake in humans and laboratory animals. There is little work investigating the role of co-exposure to alcohol and nicotine in the effects of varenicline. In pilot clinical studies, it has been reported that smoking enhances varenicline's effectiveness as a treatment for alcohol misuse, but this relationship has not been systematically investigated. To help resolve this, we examined if the effects of varenicline on alcohol and nicotine self-administration (SA) in rats are modified when the two drugs are taken together. Rats were trained on alcohol SA, and some were implanted with i.v. catheters for nicotine SA. Groups of animals then lever pressed for alcohol or nicotine alone, and another group lever pressed for alcohol and nicotine, using a two lever choice procedure. Varenicline did not affect alcohol SA. Varenicline reduced nicotine SA modestly. Access to both alcohol and nicotine reduced self-administration of either drug, but did not change the effects of varenicline. We found that in rats with a history of alcohol SA, varenicline reduced reinstatement of extinguished alcohol seeking induced by exposure to an alcohol prime combined with cues previously associated with alcohol.
authors.affiliation: Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 33 Russell Street, Toronto, Ontario M5S 2S1, Canada. Electronic address: douglas.funk@camh.ca.
authors.forename: D
authors.initials: D
authors.lastname: Funk
authors.affiliation: Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 33 Russell Street, Toronto, Ontario M5S 2S1, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Lo
authors.affiliation: Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 33 Russell Street, Toronto, Ontario M5S 2S1, Canada. Electronic address: kathy.coen@camh.ca.
authors.forename: K
authors.initials: K
authors.lastname: Coen
authors.affiliation: Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 33 Russell Street, Toronto, Ontario M5S 2S1, Canada; Department of Pharmacology and Toxicology, University of Toronto, Medical Sciences Building, Rm. 4207, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada; Department of Psychiatry, University of Toronto, 250 College Street, 8th Floor, Toronto, Ontario M5T 1R8, Canada. Electronic address: anh.le@camh.ca.
authors.forename: A D
authors.initials: AD
authors.lastname: Lê
mesh_terms: D000818:Animals; D016739:Behavior, Addictive / Q000378:metabolism*; D001522:Behavior, Animal / Q000187:drug effects*; D003216:Conditioning, Operant; D004195:Disease Models, Animal; D004347:Drug Interactions; D000431:Ethanol / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D009538:Nicotine / Q000008:administration & dosage / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D019966:Substance-Related Disorders / Q000378:metabolism*; D000068580:Varenicline / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D018722:Nicotinic Agonists; D000431:Ethanol; D009538:Nicotine; D000068580:Varenicline
keywords: Alcohol; Cues; Nicotine; Reinstatement; Self-administration; Varenicline