Semi-intact ex vivo approach to investigate spinal somatosensory circuits
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
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.
Reviewing Editor
- Eve Marder, Brandeis University, United States
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.
Version history
- Received: November 1, 2016
- Accepted: December 16, 2016
- Accepted Manuscript published: December 19, 2016 (version 1)
- 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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