Ethanol consumption by Fawn-Hooded rats following abstinence: Effect of naltrexone and changes in μ-opioid receptor density

Abstract

Background: Relapse after abstinence can be modelled in rats using an alcohol deprivation effect (ADE) of enhanced ethanol consumption after a period of enforced abstinence from ethanol; however, not all rat strains display such an effect. We wanted to examine the effect of naltrexone on ethanol consumption by ethanol-preferring Fawn-Hooded (FH) rats using such a model. Methods: FH rats were given continual free-choice access to a 5% ethanol solution or water (4 weeks) followed by 2 weeks of water alone. At the end of this abstinence period, osmotic minipumps were implanted subcutaneously to deliver saline (n = 4) or naltrexone (n = 4; 8.4 mg/kg/day for 4 weeks). After recovery from surgery,..