Baclofen alters ethanol-stimulated activity but not conditioned place preference or taste aversion in mice

Pharmacol Biochem Behav. 1999 Jun;63(2):325-31. doi: 10.1016/s0091-3057(98)00253-6.

Abstract

The present experiments examined the effects of the GABA(B) receptor agonist, baclofen, on the acquisition of ethanol-induced conditioned place preference (CPP) and conditioned taste aversion (CTA) in male DBA/2J mice. Mice in the CPP experiment received four pairings of ethanol (2g/kg) with a distinctive floor stimulus for a 5-min conditioning session (CS+ sessions). On intervening days (CS- sessions), mice received saline injections paired with a different floor type. On CS+ days, mice also received one of four doses of baclofen (0.0. 2.5, 5.0, or 7.5 mg/kg) 15 min before an injection of ethanol. For the preference test, all mice received saline injections, and were placed on a half-grid and half-hole floor for a 60-min session. Baclofen dose dependently reduced ethanol-stimulated activity, but did not alter the magnitude of ethanol-induced CPP at any dose. For the CTA experiment, mice were adapted to a 2-h per day water restriction regimen followed by five conditioning trials every 48 h. During conditioning trials, subjects received an injection of saline or baclofen (2.0 and 6.0 mg/kg) 15 min before injection of 2 g/kg ethanol or saline following 1-h access to a saccharin solution. Baclofen did not alter the magnitude of ethanol-induced CTA at any dose. In addition, baclofen alone did not produce a CTA. Overall, these studies show that activation of GABA(B) receptors with baclofen reduces ethanol-induced locomotor activation, but does not alter ethanol's rewarding or aversive effects in the CPP and CTA paradigms in DBA/2J mice.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Baclofen / pharmacology*
  • Conditioning, Psychological / drug effects*
  • Conditioning, Psychological / physiology
  • Ethanol / pharmacology*
  • GABA Agonists / pharmacology*
  • Male
  • Mice
  • Mice, Inbred DBA
  • Motivation
  • Motor Activity / drug effects*
  • Motor Activity / physiology
  • Receptors, GABA-B / physiology
  • Reward
  • Taste / drug effects
  • Taste / physiology

Substances

  • GABA Agonists
  • Receptors, GABA-B
  • Ethanol
  • Baclofen