Stuttering interneurons generate fast and robust inhibition onto projection neurons with low capacity of short term modulation in mouse lateral amygdala

PLoS One. 2013;8(3):e60154. doi: 10.1371/journal.pone.0060154. Epub 2013 Mar 19.

Abstract

The stuttering interneurons (STi) represent one minor subset of interneuron population and exhibit characteristic stuttering firing upon depolarization current injection. While it has been long held that the GABAergic inhibitory transmission largely varies with the subtype identity of presynaptic interneurons, whether such a rule also applies to STi is largely unknown. Here, by paired recording of interneuron and their neighboring projection neuron in lateral amygdala, we found that relative to the fast spiking and late spiking interneurons, the STi-evoked unitary postsynaptic currents onto the projection neurons had markedly larger amplitude, shorter onset latency and faster rising and decay kinetics. The quantal content and the number of vesicles in the readily releasable pool were also larger in synapses made by STi versus other interneurons. Moreover, the short-term plasticity, as reflected by the paired pulse depression and depolarization-induced suppression of inhibition, was the least prominent in the output synapses of STi. Thus, the fast and robust inhibition together with its low capacity of short term modulation may suggest an important role for STi in preventing the overexcitation of the projection neurons and thus gating the information traffic in amygdala.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amygdala / cytology*
  • Amygdala / physiology
  • Analysis of Variance
  • Animals
  • Fluorescence
  • Histological Techniques
  • Interneurons / physiology*
  • Male
  • Mice
  • Patch-Clamp Techniques
  • Synaptic Potentials / physiology*
  • Synaptic Transmission / physiology*
  • Synaptic Vesicles / physiology

Grants and funding

This research was supported by grants from National Natural Science Foundation of China (8071096, 31160208), Natural Science Foundation of Jiangxi Province (2011205037). During the revision process, the current work gained financial support from the “Young Scientist Cultivation Project” and “555 Talent Project” of Jiangxi Province. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.