Brain DNA damage and behavioral changes after repeated intermittent acute ethanol withdrawal by young rats

Psychopharmacology (Berl). 2015 Oct;232(19):3623-36. doi: 10.1007/s00213-015-4015-x. Epub 2015 Aug 2.

Abstract

Rationale: Alcohol addiction causes severe problems, and its deprivation may potentiate symptoms such as anxiety. Furthermore, ethanol is a neurotoxic agent that induces degeneration and the consequences underlying alcohol-mediated brain damage remain unclear.

Objectives: This study assessed the behavioral changes during acute ethanol withdrawal periods and determined the levels of DNA damage and reactive oxygen species (ROS) in multiple brain areas.

Methods: Male Wistar rats were subjected to an oral ethanol self-administration procedure with a forced diet where they were offered 8% (v/v) ethanol solution for 21 days followed by five repeated 24-h cycles alternating between ethanol withdrawal and re-exposure. Control animals received an isocaloric control diet without ethanol. Behavioral changes were analyzed on ethanol withdrawal days in the open-field (OF) and elevated plus-maze (EPM) tests within the first 6 h of ethanol deprivation. The pre-frontal cortex, hypothalamus, striatum, hippocampus, and cerebellum were dissected for alkaline and neutral comet assays and for dichlorofluorescein ROS testing.

Results: The repeated intermittent ethanol access enhanced solution intake and alcohol-seeking behavior. Decreased exploratory activity was observed in the OF test, and the animals stretched less in the EPM test. DNA single-strand breaks and ROS production were significantly higher in all structures evaluated in the ethanol-treated rats compared with controls.

Conclusions: The animal model of repeated intermittent ethanol access induced behavioral changes in rats, and this ethanol exposure model induced an increase in DNA single-strand breaks and ROS production in all brain areas. Our results suggest that these brain damages may influence future behaviors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Alcoholism / complications
  • Alcoholism / metabolism*
  • Animals
  • Anxiety / etiology
  • Anxiety / metabolism
  • Brain / drug effects*
  • Brain / metabolism*
  • DNA Damage / drug effects*
  • DNA Damage / physiology
  • Ethanol / administration & dosage*
  • Male
  • Maze Learning / drug effects
  • Maze Learning / physiology
  • Rats
  • Rats, Wistar
  • Reactive Oxygen Species / metabolism
  • Self Administration
  • Substance Withdrawal Syndrome / etiology
  • Substance Withdrawal Syndrome / metabolism*

Substances

  • Reactive Oxygen Species
  • Ethanol