Inhibitory gradient along the dorsoventral axis in the medial entorhinal cortex

Neuron. 2013 Sep 18;79(6):1197-207. doi: 10.1016/j.neuron.2013.06.038.

Abstract

Local inhibitory microcircuits in the medial entorhinal cortex (MEC) and their role in network activity are little investigated. Using a combination of electrophysiological, optical, and morphological circuit analysis tools, we find that layer II stellate cells are embedded in a dense local inhibitory microcircuit. Specifically, we report a gradient of inhibitory inputs along the dorsoventral axis of the MEC, with the majority of this local inhibition arising from parvalbumin positive (PV+) interneurons. Finally, the gradient of PV+ fibers is accompanied by a gradient in the power of extracellular network oscillations in the gamma range, measured both in vitro and in vivo. The reported differences in the inhibitory microcircuitry in layer II of the MEC may therefore have a profound functional impact on the computational working principles at different locations of the entorhinal network and influence the input pathways to the hippocampus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / drug effects
  • Action Potentials / physiology
  • Animals
  • Animals, Newborn
  • Electric Stimulation
  • Entorhinal Cortex / cytology*
  • Evoked Potentials / physiology
  • Glutamic Acid / pharmacology
  • In Vitro Techniques
  • Inhibitory Postsynaptic Potentials / drug effects
  • Inhibitory Postsynaptic Potentials / physiology*
  • Interneurons / drug effects
  • Interneurons / physiology*
  • Lysine / analogs & derivatives
  • Lysine / metabolism
  • Nerve Net / drug effects
  • Nerve Net / physiology*
  • Neural Inhibition / drug effects
  • Neural Inhibition / physiology*
  • Parvalbumins / metabolism
  • Patch-Clamp Techniques
  • Peptides / metabolism
  • Polymers
  • Rats
  • Rats, Wistar
  • Statistics, Nonparametric
  • Vesicular Inhibitory Amino Acid Transport Proteins / metabolism

Substances

  • Parvalbumins
  • Peptides
  • Polymers
  • Vesicular Inhibitory Amino Acid Transport Proteins
  • vesicular GABA transporter
  • GAT
  • Glutamic Acid
  • biocytin
  • Lysine