Repeated Long-Term Sub-concussion Impacts Induce Motor Dysfunction in Rats: A Potential Rodent Model

Andrew P Lavender; Samuel Rawlings; Andrew Warnock; Terry McGonigle; Bailey Hiles-Murison; Michael Nesbit; Virginie Lam; Mark J Hackett; Melinda Fitzgerald; Ryusuke Takechi

doi:10.3389/fneur.2020.00491

Repeated Long-Term Sub-concussion Impacts Induce Motor Dysfunction in Rats: A Potential Rodent Model

Front Neurol. 2020 May 29:11:491. doi: 10.3389/fneur.2020.00491. eCollection 2020.

Authors

Andrew P Lavender^{1

2}, Samuel Rawlings², Andrew Warnock^{3

4}, Terry McGonigle^{3

4}, Bailey Hiles-Murison^{3

5}, Michael Nesbit^{3

6}, Virginie Lam^{3

6}, Mark J Hackett^{3

7}, Melinda Fitzgerald^{3

4

8}, Ryusuke Takechi^{3

6}

Affiliations

¹ School of Health and Life Sciences, Federation University, Ballarat, VIC, Australia.
² School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.
³ Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia.
⁴ Perron Institute for Neurological and Translational Science, Ralph and Patricia Sarich Neuroscience Research Institute, Nedlands, WA, Australia.
⁵ School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.
⁶ School of Public Health, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.
⁷ School of Molecular and Life Science, Faculty of Science and Engineering, Curtin University, Perth, WA, Australia.
⁸ Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, WA, Australia.

Abstract

Whilst detrimental effects of repeated sub-concussive impacts on neurophysiological and behavioral function are increasingly reported, the underlying mechanisms are largely unknown. Here, we report that repeated sub-concussion with a light weight drop (25 g) in wild-type PVG rats for 2 weeks does not induce detectable neuromotor dysfunction assessed by beamwalk and rotarod tests. However, after 12 weeks of repeated sub-concussion, the rats exhibited moderate neuromotor dysfunction. This is the first study to demonstrate development of neuromotor dysfunction following multiple long-term sub-concussive impacts in rats. The outcomes may offer significant opportunity for future studies to understand the mechanisms of sub-concussion-induced neuropsychological changes.

Keywords: beamwalk; mild traumatic brain injury; neuromotor function; rotarod; sub-concussion.