Identification of an inhibitory neuron subtype, the L-stellate cell of the cochlear nucleus
Abstract
Auditory processing depends upon inhibitory signaling by interneurons, even at its earliest stages in the ventral cochlear nucleus (VCN). Remarkably, to date only a single subtype of inhibitory neuron has been documented in the VCN, a projection neuron termed the D-stellate cell. With the use of a transgenic mouse line, optical clearing and imaging techniques, combined with electrophysiological tools, we revealed a population of glycinergic cells in the VCN distinct from the D-stellate cell. These multipolar glycinergic cells were smaller in soma size and dendritic area, but over 10-fold more numerous than D-stellate cells. They were activated by AN and T-stellate cells, and made local inhibitory synaptic contacts on principal cells of the VCN. Given their abundance, combined with their narrow dendritic fields and axonal projections, it is likely that these neurons, here termed L-stellate cells, play a significant role in frequency-specific processing of acoustic signals.
Data availability
Datasets have been uploaded to Dryad, with the DOI doi:10.5061/dryad.69p8cz8xpThese are referred to in the appropriate figure legends.
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Data from: Discovery of a novel inhibitory neuron class, the L-Stellate cells of the cochlear nucleusDryad Digital Repository, doi:10.5061/dryad.69p8cz8xp.
Article and author information
Author details
Funding
National Institutes of Health (NS028901)
- Laurence O Trussell
National Institutes of Health (DC004450)
- Laurence O Trussell
National Institutes of Health (P30NS061800)
- Laurence O Trussell
Hearing Health Foundation (Emerging Research Grant)
- Tenzin Ngodup
Howard Hughes Medical Institute (Gilliam Fellowship)
- Gabriel E Romero
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All experimental procedures were approved by the Oregon Health and Science University's Institutional Animal Care and Use Committee, under protocol IP00000952.
Reviewing Editor
- Dwight E Bergles, Johns Hopkins University School of Medicine, United States
Version history
- Received: December 11, 2019
- Accepted: November 2, 2020
- Accepted Manuscript published: November 3, 2020 (version 1)
- Version of Record published: December 16, 2020 (version 2)
Copyright
© 2020, Ngodup et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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