Nicotinic acetylcholine receptor subtypes in nociceptive dorsal root ganglion neurons of the adult rat

Auton Neurosci. 2004 Jun 30;113(1-2):32-42. doi: 10.1016/j.autneu.2004.05.008.

Abstract

Stimulation of nicotinic acetylcholine receptors (nAChR) excites peripheral sensory nerve fibres, but also exert antinociceptive effects. The differences in these nAChR-mediated effects could be related to the expression of different nAChR subtypes located on nociceptive neurons. In the present study, we focused on the recently described alpha 10-nAChR subunit, and on alpha 4 and alpha 7 subunits, which are the most abundant subunits in the central nervous system. In nociceptive neurons from thoracic and lumbar dorsal root ganglia (DRG), nAChR subunits were found at transcriptional (RT-PCR), translational (immunohistochemistry) and functional levels. Cultured DRG neurons express mRNA for the subunits alpha 2-7 and alpha 10. The alpha-subunit proteins 4, 7 and 10 were colocalised in virtually all nociceptive neurons that were identified by immunoreactivity for the vanilloid receptor TRPV-1. These findings were corroborated by current recordings and calcium measurements, which revealed excitatory inward currents and calcium responses in capsaicin sensitive neurons.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Female
  • Ganglia, Spinal / drug effects
  • Ganglia, Spinal / metabolism*
  • Male
  • Neurons / drug effects
  • Neurons / metabolism*
  • Nicotine / pharmacology
  • Pain / metabolism*
  • RNA, Messenger / biosynthesis
  • Rats
  • Rats, Wistar
  • Receptors, Nicotinic / biosynthesis*
  • Receptors, Nicotinic / classification

Substances

  • RNA, Messenger
  • Receptors, Nicotinic
  • Nicotine