Psychopharmacology

, Volume 115, Issue 1–2, pp 173–179

Low doses of the 5-HT1A agonist 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH DPAT) increase ethanol intake

  • Denise M. Tomkins
  • Guy A. Higgins
  • Edward M. Sellers
Original Investigations

Abstract

Previous work has reported that the 5-hydroxytryptamine (5-HT)1A agonist, 8-hydroxy 2-(di-n-propylamino)tetralin (8-OH DPAT), reduces ethanol intake by rats. However, as 8-OH DPAT reduces 5-HT neurotransmission, these findings are inconsistent with the proposed inhibitory role of central 5-HT neurons on ethanol intake. We examined the effect of 8-OH DPAT on ethanol, water and food intake in rats maintained on a limited access schedule using a lower dose range (6–250 µg/kg) and by assessing concomitant changes in behaviour. Low doses of 8-OH DPAT enhanced ethanol intake even when food and water were offered as alternatives. Suppression in ethanol intake was observed at higher doses where elements of the 5-HT syndrome were apparent. Similar observations were made in both fluid and non-fluid deprived water drinking rats, suggesting the latter effect is non-selective. Therefore 8-OH DPAT may both increase or decrease ethanol consumption in the rat depending on the dose used.

Key words

Limited access schedule Ethanol intake 8-OH DPAT Behaviour 5-HT Water deprivation 

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Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • Denise M. Tomkins
    • 1
    • 2
  • Guy A. Higgins
    • 1
    • 2
  • Edward M. Sellers
    • 1
    • 2
  1. 1.Addiction Research FoundationTorontoCanada
  2. 2.Departments of Pharmacology, Medicine and PsychiatryUniversity of TorontoTorontoCanada

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