Control of glutamate clearance and synaptic efficacy by glial coverage of neurons

Science. 2001 May 4;292(5518):923-6. doi: 10.1126/science.1059162.

Abstract

Analysis of excitatory synaptic transmission in the rat hypothalamic supraoptic nucleus revealed that glutamate clearance and, as a consequence, glutamate concentration and diffusion in the extracellular space, is associated with the degree of astrocytic coverage of its neurons. Reduction in glutamate clearance, whether induced pharmacologically or associated with a relative decrease of glial coverage in the vicinity of synapses, affected transmitter release through modulation of presynaptic metabotropic glutamate receptors. Astrocytic wrapping of neurons, therefore, contributes to the regulation of synaptic efficacy in the central nervous system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / antagonists & inhibitors
  • ATP-Binding Cassette Transporters / metabolism
  • Amino Acid Transport System X-AG
  • Aminobutyrates / pharmacology
  • Animals
  • Astrocytes / physiology*
  • Dicarboxylic Acids / pharmacology
  • Excitatory Amino Acid Agonists / pharmacology
  • Excitatory Amino Acid Antagonists / pharmacology
  • Excitatory Postsynaptic Potentials
  • Female
  • Glutamic Acid / metabolism*
  • In Vitro Techniques
  • Lactation
  • Neurons / physiology*
  • Neurotransmitter Uptake Inhibitors / pharmacology
  • Pyrrolidines / pharmacology
  • Rats
  • Rats, Wistar
  • Receptors, AMPA / antagonists & inhibitors
  • Receptors, AMPA / metabolism
  • Receptors, Metabotropic Glutamate / metabolism
  • Supraoptic Nucleus / cytology
  • Supraoptic Nucleus / physiology*
  • Synapses / physiology*
  • Synaptic Transmission* / drug effects

Substances

  • 2-amino-2-methyl-4-phosphonobutyrate
  • ATP-Binding Cassette Transporters
  • Amino Acid Transport System X-AG
  • Aminobutyrates
  • Dicarboxylic Acids
  • Excitatory Amino Acid Agonists
  • Excitatory Amino Acid Antagonists
  • Neurotransmitter Uptake Inhibitors
  • Pyrrolidines
  • Receptors, AMPA
  • Receptors, Metabotropic Glutamate
  • metabotropic glutamate receptor 3
  • Glutamic Acid
  • pyrrolidine-2,4-dicarboxylic acid
  • 2-amino-4-phosphonobutyric acid