Functional effects of distinct innervation styles of pyramidal cells by fast spiking cortical interneurons

Elife. 2015 Jul 4;4:e07919. doi: 10.7554/eLife.07919.

Abstract

Inhibitory interneurons target precise membrane regions on pyramidal cells, but differences in their functional effects on somata, dendrites and spines remain unclear. We analyzed inhibitory synaptic events induced by cortical, fast-spiking (FS) basket cells which innervate dendritic shafts and spines as well as pyramidal cell somata. Serial electron micrograph (EMg) reconstructions showed that somatic synapses were larger than dendritic contacts. Simulations with precise anatomical and physiological data reveal functional differences between different innervation styles. FS cell soma-targeting synapses initiate a strong, global inhibition, those on shafts inhibit more restricted dendritic zones, while synapses on spines may mediate a strictly local veto. Thus, FS cell synapses of different sizes and sites provide functionally diverse forms of pyramidal cell inhibition.

Keywords: FS basket cell; IPSC; inhibitory synapse; neuroscience; pyramidal cell; rat; spine; synaptic conductance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Body / ultrastructure
  • Cell Communication*
  • Dendrites / ultrastructure
  • Interneurons / physiology*
  • Microscopy, Electron
  • Neural Inhibition*
  • Pyramidal Cells / physiology*
  • Rats, Wistar
  • Synapses / ultrastructure
  • Time-Lapse Imaging

Grant support

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.