Intermittent Availability of Ethanol Does Not Always Lead to Elevated Drinking in Mice

Alcohol Alcohol. Sep-Oct 2012;47(5):509-17. doi: 10.1093/alcalc/ags067. Epub 2012 Jun 19.

Abstract

Aims: Intermittent access (IA) to an alcohol (ethanol) solution can lead rats to higher ethanol intakes than continuous access, and a recent report showed increased drinking in C57BL/6J mice offered 20% ethanol vs. water 3X/week (Prior studies have offered ethanol during 24 h periods, either continuously or intermittently.).

Methods: We tested the high-preference C57BL/6J inbred mice: we also studied High Drinking in the Dark (HDID) mice, a line we have selectively bred to reach intoxicating blood ethanol levels after a short period of access to a single bottle of 20% ethanol.

Results: Neither HDID or C57BL/6J male mice offered ethanol every other day during only a 4-h access period showed greater daily intake than mice offered ethanol daily for 4 h. There was a small increase in drinking with 24 h IA in C57BL/6J mice. An experiment with HDID mice and their control heterogeneous stock stock modeled closely after a published study with C57BL/6J mice (Hwa, Chu, Levinson SA et al. Persistent escalation of alcohol drinking in C57BL/6J mice with intermittent access to 20% ethanol. Alcohol Clin Exp Res 2011;35:1938-1947) showed no significant elevation with 24 h IA exposure in either sex of any genotype. Finally, a near replication of the Hwa et al. study showed modestly greater intake in C57BL/6J mice, confirming the efficacy of 24 h IA.

Conclusion: We conclude that 4 h of IA is likely insufficient to elevate drinking in mice. The lack of effect in HDID mice and their controls further suggests that not all genotypes respond to intermittency.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Alcohol Drinking* / genetics
  • Animals
  • Behavior, Animal*
  • Central Nervous System Depressants / blood
  • Ethanol / blood
  • Female
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred Strains
  • Time Factors

Substances

  • Central Nervous System Depressants
  • Ethanol