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Semi-intact ex vivo approach to investigate spinal somatosensory circuits

  1. Junichi Hachisuka
  2. Kyle M Baumbauer
  3. Yu Omori
  4. Lindsey M Snyder
  5. H Richard Koerber  Is a corresponding author
  6. Sarah E Ross  Is a corresponding author
  1. University of Pittsburgh, United States
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Cite this article as: eLife 2016;5:e22866 doi: 10.7554/eLife.22866

Abstract

The somatosensory input that gives rise to the perceptions of pain, itch, cold and heat are initially integrated in the superficial dorsal horn of the spinal cord. Here, we describe a new approach to investigate these neural circuits in mouse. This semi-intact somatosensory preparation enables recording from spinal output neurons, while precisely controlling somatosensory input, and simultaneously manipulating specific populations of spinal interneurons. Our findings suggest that spinal interneurons show distinct temporal and spatial tuning properties. We also show that modality selectivity - mechanical, heat and cold - can be assessed in both retrogradely labeled spinoparabrachial projection neurons and genetically labeled spinal interneurons. Finally, we demonstrate that interneuron connectivity can be determined via optogenetic activation of specific interneuron subtypes. This new approach may facilitate key conceptual advances in our understanding of the spinal somatosensory circuits in health and disease.

Article and author information

Author details

  1. Junichi Hachisuka

    Department of Neurobiology, University of Pittsburgh, Pittsburgh, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Kyle M Baumbauer

    Department of Neurobiology, University of Pittsburgh, Pittsburgh, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0437-9209
  3. Yu Omori

    Department of Neurobiology, University of Pittsburgh, Pittsburgh, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Lindsey M Snyder

    Department of Neurobiology, University of Pittsburgh, Pittsburgh, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. H Richard Koerber

    Department of Neurobiology, University of Pittsburgh, Pittsburgh, United States
    For correspondence
    rkoerber@pitt.edu
    Competing interests
    The authors declare that no competing interests exist.
  6. Sarah E Ross

    Department of Neurobiology, University of Pittsburgh, Pittsburgh, United States
    For correspondence
    saross@pitt.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2593-3133

Funding

National Institutes of Health (AR063772)

  • Sarah E Ross

National Institutes of Health (AR064445)

  • Sarah E Ross

National Institutes of Health (F31NS092146)

  • Lindsey M Snyder

National Institutes of Health (NS735483)

  • Lindsey M Snyder

National Institutes of Health (NS073548)

  • Kyle M Baumbauer

Rita Allen Foundation

  • Sarah E Ross

National Institutes of Health (NS02372925)

  • H Richard Koerber

National Institutes of Health (NS096705)

  • H Richard Koerber
  • Sarah E Ross

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 of the animals were handled according to approved institutional animal care and use committee (IACUC) protocol 14043431 of the University of Pittsburgh. All surgery was performed under anesthesia, and every effort was made to minimize suffering.

Reviewing Editor

  1. Eve Marder, Brandeis University, United States

Publication history

  1. Received: November 1, 2016
  2. Accepted: December 16, 2016
  3. Accepted Manuscript published: December 19, 2016 (version 1)
  4. Version of Record published: January 4, 2017 (version 2)

Copyright

© 2016, Hachisuka 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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