Group I mGluR regulates the polarity of spike-timing dependent plasticity in substantia gelatinosa neurons

Biochem Biophys Res Commun. 2006 Aug 25;347(2):509-16. doi: 10.1016/j.bbrc.2006.06.134. Epub 2006 Jun 30.

Abstract

The spinal synaptic plasticity is associated with a central sensitization of nociceptive input, which accounts for the generation of hyperalgesia in chronic pain. However, how group I metabotropic glutamate receptors (mGluRs) may operate spinal plasticity remains essentially unexplored. Here, we have identified spike-timing dependent synaptic plasticity in substantia gelatinosa (SG) neurons, using perforated patch-clamp recordings of SG neuron in a spinal cord slice preparation. In the presence of bicuculline and strychnine, long-term potentiation (LTP) was blocked by AP-5 and Ca2+ chelator BAPTA-AM. The group I mGluR antagonist AIDA, PLC inhibitor U-73122, and IP3 receptor blocker 2-APB shifted LTP to long-term depression (LTD) without affecting acute synaptic transmission. These findings provide a link between postsynaptic group I mGluR/PLC/IP3-gated Ca2+ store regulating the polarity of synaptic plasticity and spinal central sensitization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2-Amino-5-phosphonovalerate / pharmacology
  • Animals
  • Boron Compounds / pharmacology
  • Calcium / antagonists & inhibitors
  • Calcium / metabolism
  • Calcium Channels
  • Chelating Agents / pharmacology
  • Egtazic Acid / analogs & derivatives
  • Egtazic Acid / pharmacology
  • Estrenes / pharmacology
  • Excitatory Amino Acid Antagonists / pharmacology
  • Female
  • Indans / pharmacology
  • Inositol 1,4,5-Trisphosphate Receptors
  • Long-Term Potentiation / drug effects
  • Long-Term Potentiation / physiology
  • Long-Term Synaptic Depression / drug effects
  • Long-Term Synaptic Depression / physiology
  • Male
  • Neuronal Plasticity / drug effects
  • Neuronal Plasticity / physiology*
  • Neurons / drug effects
  • Neurons / physiology*
  • Pyrrolidinones / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Cytoplasmic and Nuclear / antagonists & inhibitors
  • Receptors, Metabotropic Glutamate / antagonists & inhibitors
  • Receptors, Metabotropic Glutamate / physiology*
  • Staurosporine / pharmacology
  • Substantia Gelatinosa / cytology
  • Substantia Gelatinosa / drug effects
  • Substantia Gelatinosa / physiology*
  • Synaptic Transmission / drug effects
  • Synaptic Transmission / physiology*
  • Time Factors
  • Type C Phospholipases / antagonists & inhibitors

Substances

  • 1-aminoindan-1,5-dicarboxylic acid
  • Boron Compounds
  • Calcium Channels
  • Chelating Agents
  • Estrenes
  • Excitatory Amino Acid Antagonists
  • Indans
  • Inositol 1,4,5-Trisphosphate Receptors
  • Pyrrolidinones
  • Receptors, Cytoplasmic and Nuclear
  • Receptors, Metabotropic Glutamate
  • metabotropic glutamate receptor type 1
  • 1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione
  • 1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester
  • Egtazic Acid
  • 2-Amino-5-phosphonovalerate
  • 2-aminoethoxydiphenyl borate
  • Type C Phospholipases
  • Staurosporine
  • Calcium