Vapor Inhalation of Alcohol in Rats

Nicholas W. Gilpin1, Heather N. Richardson1, Maury Cole1, George F. Koob1

1 Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, California
Publication Name:  Current Protocols in Neuroscience
Unit Number:  Unit 9.29
DOI:  10.1002/0471142301.ns0929s44
Online Posting Date:  July, 2008
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Alcohol dependence constitutes a neuroadaptive state critical for understanding alcoholism, and various methods have been utilized to induce alcohol dependence in animals, one of which is alcohol vapor exposure. Alcohol vapor inhalation provides certain advantages over other chronic alcohol exposure procedures that share the ultimate goal of producing alcohol dependence in rats. Chronic alcohol vapor inhalation allows the experimenter to control the dose, duration, and pattern of alcohol exposure. Also, this procedure facilitates testing of somatic and motivational aspects of alcohol dependence. Chronic exposure to alcohol vapor produces increases in alcohol‐drinking behavior, increases in anxiety‐like behavior, and reward deficits in rats. Alcohol vapor inhalation as a laboratory protocol is flexible, and the parameters of this procedure can be adjusted to accommodate the specific aims of different experiments. This unit describes the options available to investigators using this procedure for dependence induction, when different options are more or less appropriate, and the implications of each. Curr. Protoc. Neurosci. 44:9.29.1‐9.29.19. © 2008 by John Wiley & Sons, Inc.

Keywords: alcohol dependence; ethanol vapor; withdrawal; abstinence; blood‐alcohol level; rat; inhalation

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Table of Contents

  • Introduction
  • Strategic Planning
  • Basic Protocol 1: Dependence Induction via Alcohol Vapor Inhalation
  • Support Protocol 1: Data Analysis for Ethanol Vapor Inhalation Experiments
  • Basic Protocol 2: Sample Protocol for Assessment of Physical Dependence in Rats Following Termination of Ethanol Vapor Inhalation
  • Commentary
  • Literature Cited
  • Figures
  • Tables
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Basic Protocol 1: Dependence Induction via Alcohol Vapor Inhalation

  • Rats (e.g., Charles River or Harlan; for optimal age of rats see above)
  • 95% (v/v) ethanol
  • Benzodiazepine
  • Reconstituted alcohol oxidase/buffer reagent
  • Alcohol vapor inhalation systems (e.g., La Jolla Alcohol Research Inc.; see )
  • Animal scale
  • Razor blade to cut the tip of the tail (in animals that are not implanted with catheters) or 1‐ml syringes to pull blood from i.v. catheters
  • Centrifuge tubes (heparinized if possible for better separation of blood and plasma)
  • High‐speed centrifuge
  • Analox AM1 analyzer (Analox Instruments)
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Literature Cited

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