Logo image
Step training-dependent plasticity in spinal cutaneous pathways
Journal article   Open access   Peer reviewed

Step training-dependent plasticity in spinal cutaneous pathways

Marie-Pascale Côté and Jean-Pierre Gossard
The Journal of neuroscience, v 24(50), pp 11317-11327
15 Dec 2004
PMID: 15601938
url
http://www.jneurosci.org/content/jneuro/24/50/11317.full.pdfView
Published, Version of Record (VoR) Open
url
https://doi.org/10.1523/JNEUROSCI.1486-04.2004View
Published, Version of Record (VoR) Open

Abstract

Adrenergic alpha-Agonists - pharmacology Animals Cats Clonidine - pharmacology Evoked Potentials - physiology Exercise Therapy Feedback, Physiological - physiology Female Hindlimb - innervation Hindlimb - physiology Motor Neurons - drug effects Motor Neurons - physiology Neural Pathways - physiopathology Neuronal Plasticity - physiology Proprioception - physiology Skin - innervation Spinal Cord - physiopathology Spinal Cord Injuries - physiopathology Spinal Cord Injuries - rehabilitation Synaptic Transmission - drug effects Synaptic Transmission - physiology Walking - physiology Weight-Bearing - physiology
Plasticity after spinal cord injury can be initiated by specific patterns of sensory feedback, leading to a reorganization of spinal networks. For example, proprioceptive feedback from limb loading during the stance phase is crucial for the recovery of stepping in spinal-injured animals and humans. Our recent results showed that step training modified transmission from group I afferents of extensors in spinal cats. However, cutaneous afferents are also activated during locomotion and are necessary for proper foot placement in spinal cats. We therefore hypothesized that step training would also modify transmission in cutaneous pathways to facilitate recovery of stepping. We tested transmission in cutaneous pathways by comparing intracellular responses in lumbar motoneurons (n = 136) in trained (n = 11) and untrained (n = 7) cats spinalized 3-5 weeks before the acute electrophysiological experiment. Three cutaneous nerves were stimulated, and each evoked up to three motoneuronal responses mediated by at least three different pathways. Overall, of 71 cutaneous pathways tested, 10 were modified by step training: transmission was reduced in 7 and facilitated in 3. Remarkably, 6 of 10 involved the medial plantar nerve innervating the plantar surface of the foot, including two of the facilitated pathways. Because the cutaneous reflexes are exaggerated after spinalization, we interpret the decrease in most pathways as a normalization of cutaneous transmission necessary to recover locomotor movements. Overall, the results showed a high degree of specificity in plasticity among cutaneous pathways and indicate that transmission of skin inputs signaling ground contact, in particular, is modified by step training.

Metrics

7 Record Views
97 citations in Scopus

Details

UN Sustainable Development Goals (SDGs)

This publication has contributed to the advancement of the following goals:

#3 Good Health and Well-Being

InCites Highlights

Data related to this publication, from InCites Benchmarking & Analytics tool:

Web of Science research areas
Neurosciences
Logo image