Rehabilitative reaching training and plasticity following spinal cord injury in the adult rat

• Author / Creator

  Krajacic, Aleksandra

• Injury to the cervical spinal cord is a devastating event that results in a transient to permanent loss of sensory and motor functions following injury. Moderate recovery has been reported to occur in individuals and in animal models after spinal cord injury (SCI). One approach to promote recovery after SCI is rehabilitative training. This thesis examines the relation of reaching training with adaptive changes (i.e. plasticity) and functional recovery following SCI. In my first experiment, I investigated whether plasticity of the corticospinal tract (CST) is the cause for reaching recovery after ablation of the dorsal and lateral CST. Rats that received reaching training were significantly better in reaching than their untrained counterparts. A relesion of the CST revealed that the reaching recovery mainly depended on plasticity of the CST itself.
  Since it is controversial whether training should be initiated immediately after SCI, I investigated whether a delayed initiation of reaching training after SCI is beneficial. I compared the reaching success of rats that received reaching training on day 4 post SCI with rats that received training on day 12 post SCI. I found that the reaching success in rats that either received reaching training on day 4 or 12 following SCI was similar.
  Lastly, I investigated whether training efficacy is declined in chronically injured rats. Since it has been shown that the inflammatory response after SCI declines, it is questionable whether there is a relation between the inflammatory response after SCI and training efficacy. In my last experiment I injected chronically injured rats with a substance that induces a systemic inflammation. I found that rehabilitative reaching training in chronic injured rats only resulted in an improved reaching recovery when the training was combined with the administration of the substance that induces inflammation (lipopolysaccharide).
  Although there are still unanswered questions regarding the underlying mechanism for functional recovery after SCI, the results of this thesis could be used as a basic to improve future rehabilitative training strategies and therefore improve the quality of life in individuals that suffer from SCI.

• Subjects / Keywords

  • Corticospinal
  • Lipopolysaccharide
  • Reaching
  • Spinal cord injury

• Graduation date

  Spring 2011

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3XP9J

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.