An NMDAR-independent LTP mediated by group II metabotropic glutamate receptors and p42/44 MAP kinase in the dentate gyrus in vitro

Neuropharmacology. 2004 Mar;46(3):311-7. doi: 10.1016/j.neuropharm.2003.09.014.

Abstract

The induction of long-term potentiation (LTP) under conditions of blockade of the N-methyl-D-aspartate receptor (NMDAR) was studied in the medial perforant path to granule cell synapse in the dentate gyrus. A small amplitude NMDAR-independent potentiation was induced by a single brief high frequency stimulation (HFS), and a summated larger LTP was induced by repeated spaced HFS. The NMDAR-independent LTP was mediated by activation of group II mGluR as it was inhibited by the group II antagonists EGLU and also low concentrations of LY341495, but not the group I mGluR antagonist MPEP. Perfusion of the group II mGluR agonist DCG-IV induced NMDAR-independent LTP in media containing an NMDAR antagonist. The NMDAR-independent LTP induced by HFS was mediated via activation of p42/44 MAP kinase as it was blocked by the selective inhibitor PD98059.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / pharmacology
  • Animals
  • Cyclopropanes / pharmacology
  • Dentate Gyrus / drug effects
  • Dentate Gyrus / physiology*
  • Enzyme Inhibitors / pharmacology
  • Excitatory Postsynaptic Potentials / drug effects
  • Excitatory Postsynaptic Potentials / physiology
  • Glycine / analogs & derivatives*
  • Glycine / pharmacology
  • In Vitro Techniques
  • Long-Term Potentiation / drug effects
  • Long-Term Potentiation / physiology*
  • Mitogen-Activated Protein Kinase 1 / antagonists & inhibitors
  • Mitogen-Activated Protein Kinase 1 / physiology*
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases / antagonists & inhibitors
  • Mitogen-Activated Protein Kinases / physiology*
  • Rats
  • Rats, Wistar
  • Receptors, Metabotropic Glutamate / agonists
  • Receptors, Metabotropic Glutamate / antagonists & inhibitors
  • Receptors, Metabotropic Glutamate / physiology*
  • Receptors, N-Methyl-D-Aspartate / agonists
  • Receptors, N-Methyl-D-Aspartate / antagonists & inhibitors
  • Receptors, N-Methyl-D-Aspartate / physiology
  • Xanthenes / pharmacology

Substances

  • Amino Acids
  • Cyclopropanes
  • Enzyme Inhibitors
  • LY 341495
  • Receptors, Metabotropic Glutamate
  • Receptors, N-Methyl-D-Aspartate
  • Xanthenes
  • metabotropic glutamate receptor 2
  • 2-(2,3-dicarboxycyclopropyl)glycine
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases
  • Glycine