Behavioral and histopathological studies of cervical spinal cord contusion injury in rats caused by an adapted weight-drop device
Article Category: Technical report
Published Online: Sep 25, 2019
Page range: 189 - 198
DOI: https://doi.org/10.1515/abm-2019-0019
Keywords
© 2018 Kanyaratana Bamrungsuk et al., published by Sciendo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.
Background
Models of spinal cord injury (SCI) caused by weight-drop devices to cause contusion have been used extensively, and transient behavioral deficits after thoracic injury have been demonstrated. The severity of the injury caused by the device should be mild enough to allow recovery.
Objective
To determine whether our adapted weight-drop device with a small tip can effectively induce mild hemicontusion at the level of the fifth cervical vertebra.
Methods
We divided 15 adult male Sprague Dawley rats into groups of 5 for the following treatments: sham (SH, laminectomy only), mild (MSCI) or severe SCI (SSCI). Behavioral tests and histopathology were used before (day 1) and after the treatment on days 3, 7, 14, 21, 28, and 35 to assess the injury.
Results
Rats with SSCI showed a significant somatosensory deficit on days 3 and 7 compared with rats in the SH group, recovering by day 14. In a horizontal-ladder test of skilled locomotion, rats with SSCI showed a significant increase in error scores and percentage of total rungs used, and a decrease in the percentage of correct paw placement compared with rats in the SH group. There was greater recovery to normal paw placement by rats with MSCI than by rats with SSCI. These behavioral deficits were consistent with histopathology using hematoxylin and eosin counterstained Luxol fast blue, indicating the degree of injury and lesion area.
Conclusions
Mild hemicontusion caused by the adapted device can be used to evaluate SCI and provides a model with which to test the efficacy of translational therapies for SCI.