Citation

Kamnaksh A, Kövesdi E, Kwon SK, Wingo DL, Ahmed F, Grunberg NE, Long JB, Agoston DV. J. Neurotrauma 2011; 28(10): 2145-2153.

Affiliation

Center for Neuroscience and Regenerative Medicine at the Uniformed Services University, Anatomy, Physiology and Genetics, Bethesda, Maryland, United States; alaa.kamnaksh.ctr@usuhs.mil.

Copyright

(Copyright © 2011, Mary Ann Liebert Publishers)

DOI

10.1089/neu.2011.1983

PMID

21861635

Abstract

The overlapping pathologies and functional outcomes of blast induced TBI (bTBI) and stress-related neurobehavioral disorders like PTSD are significant military health issues. Soldiers are exposed to multiple stressors with or without suffering bTBI, making diagnosis, treatment, as well as experimental modeling of bTBI a challenge. In this study we compared anxiety levels of Naïve rats to ones that were exposed to each of the following conditions daily for 4 consecutive days: C I: transportation alone; C II: transportation and anesthesia; C III: transportation, anesthesia, and blast sounds; Injured: all three variables plus mild blast overpressure. Following behavioral testing we analyzed sera and select brain regions for protein markers and cellular changes. C I through C III animals exhibited increased anxiety but serum CORT levels were only significantly elevated in C III and Injured rats. C III and Injured animals also had elevated IFNγ and IL-6 levels in their amygdala (AD) and ventral hippocampus (VHC). GFAP levels were only significantly elevated in the VHC, prefrontal cortex (PFC), and AD of Injured animals; they showed an apparent increase in Iba1 and GFAP immunoreactivities as well as increased numbers of TUNEL+ cells in their VHC. Our findings demonstrate that experimental conditions, particularly the exposure to blast acoustics, can increase anxiety and trigger specific behavioral and molecular changes without injury. These findings should be taken into consideration when designing bTBI studies, to better understand the role of stressors on the development of post-traumatic symptoms and to establish a differential diagnosis for PTSD and bTBI.

Language: en