Reduction in the mechanonociceptive response by intrathecal administration of glycine and related compounds

Neurochem Res. 1996 Oct;21(10):1221-6. doi: 10.1007/BF02532399.

Abstract

We have previously reported that enhanced glycine release is produced by epidural spinal cord stimulation, a clinical method for treating neuropathic pain. Our current hypothesis is that glycine administered intrathecally reduces neuropathic pain as measured by the Randall-Selitto method. Neuropathic rats created by unilateral partial ligation of the sciatic nerve were treated with intrathecal infusion of glycine, strychnine, MK-801, or 5,7-DKA at 0.1 mumol, or artificial CSF for 2 hours at a rate of 10 microliters/min. Force required to produce the pain response was significantly increased after glycine administration and reduced using strychnine, a specific glycine receptor (Gly l) antagonist. Strychnine blocked the response to glycine when infused together. Administration of the non-specific NMDA receptor MK-801 antagonist and 5,7-DKA, a specific glycine-NMDA receptor (Gly 2) antagonist, however, failed to block the response to glycine. Our results provide evidence for the use of glycine and related compounds to treat neuropathic pain.

Publication types

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

MeSH terms

  • Animals
  • Cerebrospinal Fluid / physiology
  • Dizocilpine Maleate / therapeutic use
  • Excitatory Amino Acid Antagonists / therapeutic use
  • Glycine / therapeutic use*
  • Glycine Agents / therapeutic use
  • Injections, Spinal
  • Kynurenic Acid / analogs & derivatives
  • Kynurenic Acid / therapeutic use
  • Male
  • Mechanoreceptors / drug effects*
  • Neuralgia / drug therapy*
  • Nociceptors / drug effects*
  • Rats
  • Rats, Sprague-Dawley
  • Sciatic Nerve / physiology*
  • Strychnine / therapeutic use
  • Transcutaneous Electric Nerve Stimulation

Substances

  • Excitatory Amino Acid Antagonists
  • Glycine Agents
  • Dizocilpine Maleate
  • Kynurenic Acid
  • Strychnine
  • 5,7-dichlorokynurenic acid
  • Glycine