Changed accumbal responsiveness to alcohol in rats pre-treated with nicotine or the cannabinoid receptor agonist WIN 55,212-2

Neurosci Lett. 2008 Mar 5;433(1):1-5. doi: 10.1016/j.neulet.2007.11.074. Epub 2007 Dec 23.

Abstract

Alcohol, nicotine, and cannabinoid acutely increase the activity of the mesolimbic dopamine (DA) pathway. Although polysubstance consumption is a common pattern of abuse in humans, little is known about dopamine release following pre-exposure to these drugs. The purpose of this study was to test whether alcohol-induced dopamine release into the nucleus accumbens (NAc) shell is modified by different pre-treatments: water (i.g.), alcohol (1 g/kg, i.g.), nicotine (0.4 mg/kg, s.c.), and WIN 55,212-2 (1 mg/kg, s.c.). Male Wistar rats were treated (i.g.) for 14 days with either water or alcohol. In the following 5 days rats were injected (s.c.) with vehicle, nicotine, or WIN 55,212-2. Finally, a cannula was surgically implanted into the NAc shell and alcohol-induced extracellular dopamine release was monitored in freely moving rats. Alcohol (1 g/kg; i.g.) only increased the release of dopamine when animals were previously treated with water. This DA increase was markedly inhibited by (subchronic) treatment (5 days) with nicotine or WIN 55-212-2 as well as by previous (chronic) exposure to alcohol (14 days). These data demonstrate that pre-treatment with nicotine and the cannabinoid agonist WIN 55,212-2 is able to change the sensitivity of the NAc shell in response to a moderate dose of alcohol. Therefore, cannabinoid and nicotine exposure may have important implications on the rewarding effects of alcohol, because these drugs lead to long-lasting changes in accumbal dopamine transmission.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcohol-Induced Disorders, Nervous System / chemically induced
  • Alcohol-Induced Disorders, Nervous System / metabolism
  • Alcohol-Induced Disorders, Nervous System / physiopathology
  • Alcoholism / metabolism
  • Alcoholism / physiopathology
  • Analgesics / pharmacology
  • Animals
  • Benzoxazines / pharmacology*
  • Cannabinoid Receptor Agonists
  • Central Nervous System Depressants / pharmacology
  • Disease Models, Animal
  • Dopamine / metabolism*
  • Dose-Response Relationship, Drug
  • Drug Interactions / physiology
  • Ethanol / pharmacology*
  • Extracellular Fluid / drug effects
  • Extracellular Fluid / metabolism
  • Male
  • Microdialysis
  • Morpholines / pharmacology*
  • Naphthalenes / pharmacology*
  • Nicotine / pharmacology*
  • Nicotinic Agonists / pharmacology
  • Nucleus Accumbens / drug effects*
  • Nucleus Accumbens / metabolism
  • Nucleus Accumbens / physiopathology
  • Rats
  • Reward
  • Up-Regulation / drug effects
  • Up-Regulation / physiology

Substances

  • Analgesics
  • Benzoxazines
  • Cannabinoid Receptor Agonists
  • Central Nervous System Depressants
  • Morpholines
  • Naphthalenes
  • Nicotinic Agonists
  • Ethanol
  • (3R)-((2,3-dihydro-5-methyl-3-((4-morpholinyl)methyl)pyrrolo-(1,2,3-de)-1,4-benzoxazin-6-yl)(1-naphthalenyl))methanone
  • Nicotine
  • Dopamine