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The recovery of standing and locomotion after spinal cord injury does not require task-specific training

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Cite this article as: eLife 2019;8:e50134 doi: 10.7554/eLife.50134

Abstract

After complete spinal cord injury, mammals, including mice, rats and cats, recover hindlimb locomotion with treadmill training. The premise is that sensory cues consistent with locomotion reorganize spinal sensorimotor circuits. Here, we show that hindlimb standing and locomotion recover after spinal transection in cats without task-specific training. Spinal-transected cats recovered full weight bearing standing and locomotion after five weeks of rhythmic manual stimulation of triceps surae muscles (non-specific training) and without any intervention. Moreover, cats modulated locomotor speed and performed split-belt locomotion six weeks after spinal transection, functions that were not trained or tested in the weeks prior. This indicates that spinal networks controlling standing and locomotion and their interactions with sensory feedback from the limbs remain largely intact after complete spinal cord injury. We conclude that standing and locomotor recovery is due to the return of neuronal excitability within spinal sensorimotor circuits that do not require task-specific activity-dependent plasticity.

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Article and author information

Author details

  1. Jonathan Harnie

    Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, Canada
    Competing interests
    The authors declare that no competing interests exist.
  2. Adam Doelman

    Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, Canada
    Competing interests
    The authors declare that no competing interests exist.
  3. Emmanuelle de Vette

    Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Johannie Audet

    Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, Canada
    Competing interests
    The authors declare that no competing interests exist.
  5. Etienne Desrochers

    Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, Canada
    Competing interests
    The authors declare that no competing interests exist.
  6. Nathalie Gaudreault

    School of Rehabilitation, Université de Sherbrooke, Sherbrooke, Canada
    Competing interests
    The authors declare that no competing interests exist.
  7. Alain Frigon

    Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, Canada
    For correspondence
    Alain.Frigon@USherbrooke.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9259-2706

Funding

Canadian Institutes of Health Research (PJT-156296)

  • Alain Frigon

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

Ethics

Animal experimentation: All procedures were approved by the Animal Care Committee of the Université de Sherbrooke and were in accordance with policies and directives of the Canadian Council on Animal Care (Protocol 442-18). Twelve adult cats (> 1 year of age at time of experimentation), 5 males and 7 females, weighing between 3.6 kg and 4.7 kg were used in the present study. Our study followed the ARRIVE guidelines for animal studies (Kilkenny et al. 2010).

Reviewing Editor

  1. Jan-Marino Ramirez, Seattle Children's Research Institute, United States

Publication history

  1. Received: July 11, 2019
  2. Accepted: December 8, 2019
  3. Accepted Manuscript published: December 11, 2019 (version 1)
  4. Version of Record published: December 20, 2019 (version 2)

Copyright

© 2019, Harnie 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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