A network of electrically coupled interneurons drives synchronized inhibition in neocortex

Nat Neurosci. 2000 Sep;3(9):904-10. doi: 10.1038/78809.

Abstract

The neocortex has at least two different networks of electrically coupled inhibitory interneurons: fast-spiking (FS) and low-threshold-spiking (LTS) cells. Agonists of metabotropic glutamate or acetylcholine receptors induced synchronized spiking and membrane fluctuations, with irregular or rhythmic patterns, in networks of LTS cells. LTS activity was closely correlated with inhibitory postsynaptic potentials in neighboring FS interneurons and excitatory neurons. Synchronized LTS activity required electrical synapses, but not fast chemical synapses. Tetanic stimulation of local circuitry induced effects similar to those of metabotropic agonists. We conclude that an electrically coupled network of LTS interneurons can mediate synchronized inhibition when activated by modulatory neurotransmitters.

Publication types

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

MeSH terms

  • Action Potentials / drug effects
  • Action Potentials / physiology*
  • Animals
  • Cortical Synchronization / methods*
  • Electric Conductivity
  • Interneurons / cytology
  • Interneurons / drug effects
  • Interneurons / metabolism*
  • Neocortex / cytology
  • Neocortex / drug effects
  • Neocortex / metabolism*
  • Nerve Net / cytology
  • Nerve Net / drug effects
  • Nerve Net / physiology*
  • Neural Inhibition / drug effects
  • Neural Inhibition / physiology*
  • Neurotransmitter Agents / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Metabotropic Glutamate / drug effects
  • Receptors, Metabotropic Glutamate / metabolism
  • Synapses / drug effects
  • Synapses / metabolism*

Substances

  • Neurotransmitter Agents
  • Receptors, Metabotropic Glutamate