A Novel Acute Discogenic Myelopathy Model Using Merocel <sup>®</sup> Sponge: Comparison With Clip Compression Model in Rats

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Abstract

Objective

Animal models of spinal cord injuries (SCIs) use rats to simulate human SCIs. Among the various techniques, clips have been used to reproduce the compression-contusion model. However, the mechanism of injury in discogenic incomplete SCI may differ from that in clip injury; however, a model has yet to be established. Previously, we issued a patent (No. 10-2053770) for a rat SCI model using Merocel ^®, a water-absorbing self-expanding polymer sponge. The objectives of this study were to compare the locomotor and histopathological changes between the Merocel ^®-compression model (MC group) and clip compression model (clip group).

Methods

This study included 4 groups of rats: MC (n=30), MC-sham (n=5), clip (n=30), and clip-sham (n=5). Locomotor function was evaluated in all groups using the Basso, Beattie, and Bresnahan (BBB) scoring system, 4 weeks after injury. Histopathological analyses included morphology, presence of inflammatory cells, microglial activation, and extent of neuronal damage, which were compared among the groups.

Results

The BBB scores in the MC group were significantly higher than those in the clip group throughout the 4 weeks ( p<0.01). Neuropathological changes in the MC group were significantly less severe than those in the clip group. In addition, motor neurons were well preserved in the ventral horn of the MC group but poorly preserved in the ventral horn of the clip group.

Conclusion

The novel MC group can help elucidate the pathophysiology of acute discogenic incomplete SCIs and may be applied in various SCI therapeutic strategies.

GRAPHICAL ABSTRACT

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Author and article information

Journal

Journal ID (nlm-ta): Korean J Neurotrauma

Journal ID (iso-abbrev): Korean J Neurotrauma

Journal ID (publisher-id): KJN

Title: Korean Journal of Neurotrauma

Publisher: Korean Neurotraumatology Society

ISSN (Print): 2234-8999

ISSN (Electronic): 2288-2243

Publication date Collection: June 2023

Publication date (Electronic): 23 June 2023

Volume: 19

Issue: 2

Pages: 204-217

Affiliations

[1 ]Department of Neurosurgery, Seoul National University Hospital, Seoul, Korea.

[2 ]Department of Neurosurgery, College of Medicine, Jeju National University, Jeju, Korea.

Author notes

Address for correspondence: Ki-Bum Sim. Department of Neurosurgery, College of Medicine, Jeju National University, 15 Aran 13-gil, Jeju 63241, Korea. kibumsim@ 123456gmail.com

Author information

Do-Hyung Kim https://orcid.org/0000-0002-3485-6101

Ki-Bum Sim https://orcid.org/0000-0002-2281-1221

Article

DOI: 10.13004/kjnt.2023.19.e28

PMC ID: 10329878

SO-VID: 2a1d1fec-1307-4d81-97ca-97894a822187

License:

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( https://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

History

Date received : 05 March 2023

Date revision received : 02 June 2023

Date accepted : 08 June 2023

Funding

Funded by: National Research Foundation of Korea, CrossRef https://doi.org/10.13039/501100003725;

Award ID: NRF-2014R1A1A2055965