Chronic mild stress increases alcohol intake in mice with low dopamine D2 receptor levels

Foteini Delis, Panayotis K. Thanos, Christina Rombola, Lauren Rosko, David Grandy, Gene Jack Wang, Nora D. Volkow

    Research output: Contribution to journalArticle

    23 Scopus citations

    Abstract

    Alcohol use disorders emerge from a complex interaction between environmental and genetic factors. Stress and dopamine D2 receptor levels (DRD2) have been shown to play a central role in alcoholism. To better understand the interactions between DRD2 and stress in ethanol intake behavior, we subjected Drd2 wild-type (+/+), heterozygous (+/-), and knockout (-/-) mice to 4 weeks of chronic mild stress (CMS) and to an ethanol two-bottle choice during CMS weeks 2-4. Prior to and at the end of the experiment, the animals were tested in the forced swim and open field tests. We measured ethanol intake and preference, immobility in the force swim test, and activity in the open field. We show that under no CMS, Drd2+/- and Drd2-/- mice had lower ethanol intake and preference compared with Drd2+/+. Exposure to CMS decreased ethanol intake and preference in Drd2+/+ and increased them in Drd2+/- and Drd2-/- mice. At baseline, Drd2+/- and Drd2-/- mice had significantly lower activity in the open field than Drd2+/+, whereas no genotype differences were observed in the forced swim test. Exposure to CMS increased immobility during the forced swim test in Drd2+/- mice, but not in Drd2+/+ or Drd2-/- mice, and ethanol intake reversed this behavior. No changes were observed in open field test measures. These findings suggest that in the presence of a stressful environment, low DRD2 levels are associated with increased ethanol intake and preference and that under this condition, increased ethanol consumption could be used as a strategy to alleviate negative mood.

    Original languageEnglish (US)
    Pages (from-to)95-105
    Number of pages11
    JournalBehavioral Neuroscience
    Volume127
    Issue number1
    DOIs
    Publication statusPublished - Feb 2013

      Fingerprint

    Keywords

    • Chronic mild stress
    • Dopamine D2 receptors
    • Ethanol

    ASJC Scopus subject areas

    • Behavioral Neuroscience

    Cite this

    Delis, F., Thanos, P. K., Rombola, C., Rosko, L., Grandy, D., Wang, G. J., & Volkow, N. D. (2013). Chronic mild stress increases alcohol intake in mice with low dopamine D2 receptor levels. Behavioral Neuroscience, 127(1), 95-105. https://doi.org/10.1037/a0030750