Serotonin(2C) receptors in the ventral pallidum regulate motor function in rats

Neuroreport. 2013 Aug 7;24(11):605-8. doi: 10.1097/WNR.0b013e3283630af5.

Abstract

The ventral pallidum is a limbic brain region that regulates motor function. This region is extensively innervated by serotoninergic neurons from the dorsal raphe nucleus. Serotonergic receptors, including the 5-HT(2C) receptor subtype, are located in the ventral pallidum. However, little is known regarding the behavioral consequences of serotonergic transmission in the ventral pallidum, and the role of 5-HT(2C) receptors has not been studied. To address this paucity, we measured the motoric consequences of injections of 0.33-10 ng of the 5-HT(2C) receptor agonist MK 212 into the ventral pallidum of adult male Sprague-Dawley rats. We determined that locomotor activity was attenuated by 6.6 ng MK 212, and rearing was attenuated by both 1 and 6.6 ng. The motor suppressant effects of MK 212 were lost at the higher dose of 10 ng, likely reflecting a loss of selectivity of this ligand. These findings indicate negative regulation of motor function by 5-HT(2C) receptors in the ventral pallidum.

Publication types

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

MeSH terms

  • Animals
  • Limbic System / drug effects
  • Limbic System / metabolism*
  • Male
  • Motor Activity / drug effects
  • Motor Activity / physiology*
  • Pyrazines / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Receptor, Serotonin, 5-HT2C / metabolism*
  • Serotonin Receptor Agonists / pharmacology
  • Synaptic Transmission / drug effects
  • Synaptic Transmission / physiology*

Substances

  • Pyrazines
  • Receptor, Serotonin, 5-HT2C
  • Serotonin Receptor Agonists
  • 6-chloro-2-(1-piperazinyl)pyrazine