Kainate receptor-mediated presynaptic inhibition converges with presynaptic inhibition mediated by Group II mGluRs and long-term depression at the hippocampal mossy fiber-CA3 synapse

J Neural Transm (Vienna). 2007;114(11):1425-31. doi: 10.1007/s00702-007-0750-4. Epub 2007 May 18.


Kainate receptors (KARs) effect depression of glutamate release at hippocampal mossy fiber-CA3 (MF-CA3) synapses by a metabotropic action involving adenylyl cyclase (AC) inhibition, cAMP reduction, and diminished protein kinase A (PKA) activation. Using hippocampal slices, we show here that KAR activation interferes with the depression of glutamate release produced by Group II metabotropic glutamate receptor stimulation and low frequency stimulation (LFS)-induced long-term depression (LTD), also expressed through presynaptic AC/cAMP/PKA at MF-CA3 synapses. The mutual occlusion of depression mediated by presynaptic KARs, Group II mGluR and LFS-induced LTD suggests their mechanistic convergence at the MF-CA3 synapse and thus invokes KARs in synaptic plasticity manifest in LTD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cyclic AMP-Dependent Protein Kinases / physiology
  • Data Interpretation, Statistical
  • Electrophysiology
  • Excitatory Amino Acid Antagonists / pharmacology
  • Excitatory Postsynaptic Potentials / physiology
  • In Vitro Techniques
  • Kainic Acid / pharmacology
  • Mice
  • Mice, Inbred C57BL
  • Mossy Fibers, Hippocampal / physiology*
  • Neuronal Plasticity / physiology*
  • Patch-Clamp Techniques
  • Receptors, Kainic Acid / physiology*
  • Receptors, Metabotropic Glutamate / physiology*
  • Receptors, Presynaptic / physiology*
  • Synapses / physiology*


  • Excitatory Amino Acid Antagonists
  • Receptors, Kainic Acid
  • Receptors, Metabotropic Glutamate
  • Receptors, Presynaptic
  • metabotropic glutamate receptor 2
  • Cyclic AMP-Dependent Protein Kinases
  • Kainic Acid