Citation

Desai A, Chen H, Kim HY. J. Neurotrauma 2019; ePub(ePub): ePub.

Affiliation

NIAAA/NIH, 5625 Fishers Lane, Rockville, Maryland, United States, 20852; hykim@nih.gov.

Copyright

(Copyright © 2019, Mary Ann Liebert Publishers)

DOI

10.1089/neu.2019.6602

PMID

31530220

Abstract

Visual dysfunction is a common occurrence after traumatic brain injury (TBI). We investigated in this study effects of single or multiple mild TBI on visual function in mice using a closed head injury model that permits unconstrained head movement after impact. Adult mice were briefly anesthetized with isoflurane and given one or three mild head injuries with the closed head injury by mechanically engineered rotational acceleration (CHIMERA) device with an inter-injury interval of 24 hours. The mice were then tested in the Morris water maze, visual cliff and open field tests from day 19 to day 32, and for visual evoked potential at 5 weeks after the last injury and euthanized. The mice with multiple head injuries showed impaired performance in visible platform water maze test and had increased errors in the visual cliff test. Furthermore, there was a graded difference in visual evoked potential with the single injury mice showing modest reduction in N1 amplitude while the multiple injury produced significant reduction compared to sham and single injury group. The optic tract of the injured mice showed increases in glial cell immunostaining. The increase in GFAP immunostaining reached statistical significance for both injured groups while the Iba-1 immunostaining was only significantly increased in the optic tract of repeatedly injured mice. These results indicate that multiple injuries using CHIMERA may result in visual deficits which can affect certain behavioral performances. The change in vision may be a useful marker when monitoring injury outcome and screening for protective agents from TBI.

Language: en

Keywords

BEHAVIORAL ASSESSMENTS; GLIA CELL RESPONSE TO INJURY; TRAUMATIC BRAIN INJURY