Activation of dopamine D3 autoreceptors inhibits firing of ventral tegmental dopaminergic neurones in vivo

Eur J Pharmacol. 1995 Mar 14;275(3):R7-9. doi: 10.1016/0014-2999(95)00106-u.

Abstract

The firing rate of dopaminergic neurones in the ventral tegmental area of anaesthetised rats was dose-dependently (0.31-5.0 micrograms/kg i.v.) inhibited by the dopamine D3 receptor agonist, (+)-7-OH-DPAT (7-hydroxy-2-(di-n-propylamino)tetralin). The selective dopamine D3 receptor antagonist, (+)-S 14297 ((+)-[7-(N,N-dipropylamino)-5,6,7,8-tetrahydro-naphtho(2,3b)dihydro,2,3- furane]), dose-dependently (16-125 micrograms/kg i.v.) inhibited the action of (+)-7-OH-DPAT (5 micrograms/kg i.v.); its inactive distomer, (-)-S 17777 (125 micrograms/kg i.v.), was ineffective. Alone, (+)-S 14297 (125 micrograms/kg i.v.) did not modify the firing rate. Haloperidol (16 micrograms/kg i.v.) fully reversed the action of (+)-7-OH-DPAT and, alone, significantly increased firing rate. These data suggest that inhibitory (dendritic) dopamine D3 (auto)receptors control the electrical activity of ventral tegmental area-localised dopaminergic neurones.

MeSH terms

  • 2-Naphthylamine / analogs & derivatives
  • 2-Naphthylamine / pharmacology
  • Animals
  • Autoreceptors / physiology*
  • Furans / pharmacology
  • Male
  • Rats
  • Rats, Wistar
  • Receptors, Dopamine / physiology*
  • Receptors, Dopamine D2*
  • Receptors, Dopamine D3
  • Tetrahydronaphthalenes / pharmacology
  • Ventral Tegmental Area / physiology*

Substances

  • Autoreceptors
  • Drd3 protein, rat
  • Furans
  • Receptors, Dopamine
  • Receptors, Dopamine D2
  • Receptors, Dopamine D3
  • Tetrahydronaphthalenes
  • 7-(N,N-dipropylamino)-5,6,7,8-tetrahydronaphtho(2,3-b)dihydro-2,3-furan
  • 2-Naphthylamine
  • 7-hydroxy-2-N,N-dipropylaminotetralin