Flexor reflex excitability in mice lacking galanin receptor galanin-R1

Neurosci Lett. 2003 Jul 24;345(3):153-6. doi: 10.1016/s0304-3940(03)00516-0.

Abstract

This study was conducted to examine the excitability of the nociceptive flexor reflex and its sensitization by repetitive stimulation of C-fibers in anesthetized mice that lack the galanin-R1 receptor. Repetitive stimulation of C-fibers induced a gradual increase in reflex magnitude during the stimulation (wind-up), and a subsequent increase in spinal reflex excitability (central sensitization). This occurred in GAL-R1 -/-, GAL-R1 +/-, and +/+ wild-type controls, with no significant differences observed between genotypes. Intrathecal administration of galanin markedly blocked the sensitization following the repetitive stimulation in all three groups. No differences between wild-type or galanin-R1 receptor knockout mice were seen. These results confirm previous studies in rats, showing that intrathecal galanin reduces the central sensitization following wind-up. The present data indicate that this effect is probably mediated by receptors other than GAL-R1.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Analysis of Variance
  • Animals
  • Dose-Response Relationship, Drug
  • Electric Stimulation
  • Electromyography / methods
  • Galanin / pharmacology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Muscles / drug effects
  • Muscles / physiology
  • Nerve Fibers / physiology
  • Neural Inhibition / drug effects
  • Neural Inhibition / physiology
  • Receptors, Galanin
  • Receptors, Neuropeptide / deficiency*
  • Receptors, Neuropeptide / genetics
  • Receptors, Neuropeptide / metabolism*
  • Reflex / physiology*
  • Sural Nerve / physiology

Substances

  • Receptors, Galanin
  • Receptors, Neuropeptide
  • Galanin