Descending systems contributing to locomotor recovery after mild
or moderate spinal cord injury in rats: experimental evidence and a review of
literature
Affiliations: Division of Physical Therapy, School of Allied Medical
Professions, The Ohio State University, Columbus, USA | Department of Neuroscience, The Ohio State University,
Columbus, USA
Note: [] Corresponding author: Dr. D. Michele Basso, Division of Physical
Therapy, School of Allied Medical Professions, 306 Atwell Hall, 1583 Perry
Street, Columbus OH 43210, USA, Tel.: +1 614 292 0754; Fax: +1 614 292 0210;
E-mail: basso.2@osu.edu
Abstract: Purpose: Locomotor recovery after spinal cord contusion injury
(SCI) may be mediated by descending axons spared at the lesion epicenter.
Greater axonal sparing is associated with more extensive recovery. Therefore,
we identified the source and relative proportion of spared axons associated
with extensive or limited locomotor recovery after SCI. Methods: Female
Sprague Dawley rats underwent mild or moderate SCI using the OSU device.
Results: Locomotor recovery was greater for the mild than moderate group with
the primary differences being restitution of limb coordination, very little toe
dragging and minor paw rotation. Conclusions: The following brain nuclei
with substantial neuronal labeling after mild but not moderate SCI may play an
important role in locomotor recovery: raphe pallidus and magnus, ventral
medullary and pontine reticular formation, lateral vestibular nucleus, red
nucleus and locus coeruleus. We review the normal anatomical distribution of
descending systems to the lumbar cord in rat and the role they play in motor
control.
