Present address: Department of Biomedical Sciences, University of Prince Edward Island, 550 University Avenue, Charlottetown, PE, Canada, C1A 4P3.
Unilateral dorsal column and rubrospinal tract injuries affect overground locomotion in the unrestrained rat
Version of Record online: 22 JUL 2003
European Journal of Neuroscience
Volume 18, Issue 2, pages 412–422, July 2003
How to Cite
Webb, A. A. and Muir, G. D. (2003), Unilateral dorsal column and rubrospinal tract injuries affect overground locomotion in the unrestrained rat. European Journal of Neuroscience, 18: 412–422. doi: 10.1046/j.1460-9568.2003.02768.x
- Issue online: 22 JUL 2003
- Version of Record online: 22 JUL 2003
- Received 20 March 2003, revised 2 May 2003, accepted 12 May 2003
- dorsolateral funiculus;
- ground reaction forces;
The purpose of this study was to determine the importance of the rubrospinal pathway and the ascending components of the dorsal column for overground locomotion in adult, unrestrained rats. The dorsal column (excluding the corticospinal tract), the rubrospinal tract or both were damaged unilaterally in rats at the level of the upper cervical spinal cord. Behavioural analysis consisted of skilled locomotion (an evaluation of footslips during ladder walking), a paw usage task and the assessment of ground reaction forces during unrestrained locomotion. All lesioned animals used the forepaw ipsilateral to the lesions less while rearing. Animals with dorsal column injuries used the forelimb contralateral to the spinal injury significantly more while rearing compared with uninjured animals. All lesioned animals produced more footfalls while crossing the ladder compared with uninjured animals. All injuries, regardless of the pathway affected, resulted in significant alterations in body weight support and reduced braking forces from the forelimb ipsilateral to the injury during overground locomotion. Animals typically bore less weight on the hindlimb ipsilateral to the lesion compared with the hindlimb contralateral to the spinal injury. Taken together with previously published work, our data indicate that the rubrospinal and dorsal column pathways are important for forelimb support while rearing and for skilled locomotion. Additionally, the ascending dorsal column pathways and the rubrospinal tract play a role during flat surface overground locomotion and combined damage to these pathways does not alter the acquired gait.