Citation

Arun P, Wilder D, Eken O, Urioste R, Batuure A, Sajja VSSS, Van Albert S, Wang Y, Gist I, Long J. J. Neurotrauma 2019; ePub(ePub): ePub.

Affiliation

Walter Reed Army Institute of Research, Blast-Induced Neurotrauma Branch, Silver Spring, Maryland, United States; joseph.b.long.civ@mail.mil.

Copyright

(Copyright © 2019, Mary Ann Liebert Publishers)

DOI

10.1089/neu.2019.6591

PMID

31595810

Abstract

Anecdotal observations of blast victims indicate that significant neuropathological and neurobehavioral defects may develop at later stages of life. To preclinically model this phenomenon, we have examined neurobehavioral changes in rats up to 1 year after exposure to single and tightly coupled repeated blasts using an advanced blast simulator. Neurobehavioral changes were monitored at acute, sub-acute and chronic time points using Morris water maze test of spatial learning and memory, novel object recognition test of short-term memory, open field exploratory activity as a test of anxiety/depression, a rotating pole test for vestibulomotor function, and a rotarod balance test for motor coordination. Single and repeated blasts resulted in significant functional deficits at both acute and chronic time points. In most functional tests, rats exposed to repeated blasts performed more poorly than rats exposed to single blast. Interestingly, several functional deficits post-blast were most pronounced at 6 months and beyond. Significant neuromotor impairments occurred at early stages after blast exposure and the severity increased with repeated exposures. The novel object recognition testing revealed short-term memory deficits at 6 and 12 months post-blast. The water maze test revealed impairments at acute and chronic stages after blast exposure. The most substantial changes in the blast-exposed rats were observed with the center time and margin time legacies in the open field exploration test at 6, 9 and 12 months post-blast. Notably, these two outcome measures were minimally altered acutely, recovered during sub-acute stages, and were markedly affected during the chronic stages after blast exposures and may implicate development of chronic anxiety and depressive-like behaviors.

Language: en

Keywords

ANIMAL STUDIES; BEHAVIORAL ASSESSMENTS; MILITARY INJURY; TRAUMATIC BRAIN INJURY