Schedule-induced polydipsia in lines of rats selectively bred for high and low ethanol preference

Behav Genet. 2008 Sep;38(5):515-24. doi: 10.1007/s10519-008-9224-1. Epub 2008 Sep 9.

Abstract

Ethanol drinking was assessed in the P/NP, HAD1/LAD1, and HAD2/LAD2 lines of rats under environmental conditions that produce schedule-induced polydipsia. Female rats (n = 8/line), maintained at 85% of free-feeding body weights, underwent daily 1-h sessions during which 45-mg food pellets were delivered every 60 s. Water, 2, 4, 8, 16, or 32% w/v ethanol solution was available from a single bottle for 8 consecutive sessions at each concentration, with blood-ethanol levels (BELs) determined after selected sessions. P and HAD2 rats drank more water and ethanol than their non-preferring counterparts, while HAD1 and LAD1 rats did not differ. Ethanol intake and BELs were positively correlated (r = 0.75) across lines. Finally, rats were allowed 14 daily choice sessions with 8% ethanol and water concurrently available. Water intake generally exceeded ethanol intake in all lines, while P rats drank similar amounts of both fluids. These line differences indicate pleiotropic effects of genes that mediate ethanol intake and schedule-induced behaviors.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Alcohol Drinking / genetics*
  • Alcohols / pharmacology
  • Animals
  • Behavior, Animal
  • Body Weight
  • Choice Behavior / drug effects
  • Conditioning, Operant / drug effects
  • Drinking / drug effects
  • Drinking / genetics
  • Environment
  • Ethanol / pharmacology*
  • Female
  • Rats
  • Rats, Wistar
  • Thirst*
  • Time Factors

Substances

  • Alcohols
  • Ethanol