title: Ethanol and sucrose seeking and consumption following repeated administration of the GABA(B) agonist baclofen in rats.
abstract: BACKGROUND
  Baclofen, a GABA(B) agonist, has been found to decrease alcohol craving in humans and to nonselectively decrease ethanol intake in some rodent models. This experiment assessed the effects of repeated administration of baclofen on reinforcer seeking and consumption using the sipper tube appetitive/consummatory model of ethanol access.
  
  
  METHODS
  Subjects were divided into 2 groups and trained to make 30 lever press responses that resulted in access to either 10% ethanol or 2% sucrose in a sipper tube-drinking spout for 20 minutes. Three doses of baclofen were tested (0.3, 1.0, and 3.0 mg/kg) and each drug treatment was assessed using the following schedule: Monday, saline; Tuesday to Thursday, baclofen; and Friday, saline.
  
  
  RESULTS
  The low dose of baclofen had no effect on the seeking or intake of either sucrose or ethanol, and the 1.0 mg/kg dose also had no effect on the appetitive, seeking response. However, the 1.0 mg/kg dose significantly decreased sucrose intake (from an average of 0.56 to 0.41 g/kg) and significantly increased ethanol intake (from an average of 0.77 to 1.00 g/kg). Similarly, the high dose (3.0 mg/kg) decreased sucrose intake and had a tendency to increase ethanol intake while decreasing both sucrose seeking and ethanol seeking.
  
  
  CONCLUSIONS
  Overall, baclofen treatment affected reinforcer intake at doses that had no effect on reinforcer seeking, and effective doses decreased both sucrose seeking and ethanol seeking. Moreover, the effects on reinforcer intake were disparate, in that baclofen increased ethanol drinking and decreased sucrose drinking. The nonspecific effects of baclofen suggest that the GABA(B) system may be involved in general consummatory or drinking behaviors and does not appear to specifically regulate ethanol-motivated responding.
authors.affiliation: Center for Alcohol and Addiction Studies, Brown University, Providence, Rhode Island 02912, USA. Cristine_Czachowski@brown.edu
authors.forename: Cristine L
authors.initials: CL
authors.lastname: Czachowski
authors.forename: Brooke H
authors.initials: BH
authors.lastname: Legg
authors.forename: Kirstie H
authors.initials: KH
authors.lastname: Stansfield
mesh_terms: D000818:Animals; D001418:Baclofen / Q000008:administration & dosage*; D001522:Behavior, Animal; D003259:Consummatory Behavior; D000431:Ethanol / Q000008:administration & dosage*; D058786:GABA-B Receptor Agonists; D008297:Male; D051381:Rats; D020318:Rats, Long-Evans; D012054:Reinforcement, Psychology; D012646:Self Administration; D013395:Sucrose / Q000008:administration & dosage*
chemical_list: D058786:GABA-B Receptor Agonists; D000431:Ethanol; D013395:Sucrose; D001418:Baclofen