Effects of the serotonin 5-HT(7) receptor antagonist SB-269970 on the inhibition of dopamine neuronal firing induced by amphetamine

Eur J Pharmacol. 2007 Sep 10;570(1-3):72-6. doi: 10.1016/j.ejphar.2007.05.037. Epub 2007 Jun 5.

Abstract

Using extracellular unitary recordings in anaesthetized rats, this study examined the implication of the serotonin 7 (5-HT(7)) receptors in the inhibitory effect of amphetamine on ventral tegmental area and substantia nigra pars compacta dopamine neuronal activity. The acute administration of the selective 5-HT(7) receptor antagonist, SB-269970 (0.1, 0.5 and 1 mg/kg, i.p.), did not alter the firing activity of dopamine neurons. Interestingly, this antagonist prevented significantly the inhibition of dopamine neuronal firing activity induced by amphetamine (1 mg/kg, i.v.) in the ventral tegmental area, but not in the substantia nigra pars compacta. The present results suggest that 5-HT(7) receptors modulate the dopamine firing activity in the ventral tegmental area, thus affecting preferentially the mesocorticolimbic pathway.

MeSH terms

  • Amphetamine / pharmacology
  • Animals
  • Dopamine / physiology*
  • Male
  • Neurons / drug effects
  • Neurons / physiology
  • Phenols / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Serotonin / physiology*
  • Serotonin Antagonists / pharmacology*
  • Substantia Nigra / cytology
  • Substantia Nigra / drug effects
  • Substantia Nigra / physiology
  • Sulfonamides / pharmacology*
  • Ventral Tegmental Area / cytology
  • Ventral Tegmental Area / drug effects
  • Ventral Tegmental Area / physiology*

Substances

  • Phenols
  • Receptors, Serotonin
  • SB 269970
  • Serotonin Antagonists
  • Sulfonamides
  • serotonin 7 receptor
  • Amphetamine
  • Dopamine