Isolated Primary Blast Inhibits Long-Term Potentiation in Organotypic Hippocampal Slice Cultures.

Journal Article (Journal Article)

Over the last 13 years, traumatic brain injury (TBI) has affected over 230,000 U.S. service members through the conflicts in Iraq and Afghanistan, mostly as a result of exposure to blast events. Blast-induced TBI (bTBI) is multi-phasic, with the penetrating and inertia-driven phases having been extensively studied. The effects of primary blast injury, caused by the shockwave interacting with the brain, remain unclear. Earlier in vivo studies in mice and rats have reported mixed results for primary blast effects on behavior and memory. Using a previously developed shock tube and in vitro sample receiver, we investigated the effect of isolated primary blast on the electrophysiological function of rat organotypic hippocampal slice cultures (OHSC). We found that pure primary blast exposure inhibited long-term potentiation (LTP), the electrophysiological correlate of memory, with a threshold between 9 and 39 kPa·ms impulse. This deficit occurred well below a previously identified threshold for cell death (184 kPa·ms), supporting our previously published finding that primary blast can cause changes in brain function in the absence of cell death. Other functional measures such as spontaneous activity, network synchronization, stimulus-response curves, and paired-pulse ratios (PPRs) were less affected by primary blast exposure, as compared with LTP. This is the first study to identify a tissue-level tolerance threshold for electrophysiological changes in neuronal function to isolated primary blast.

Full Text

Duke Authors

Cited Authors

  • Vogel, EW; Effgen, GB; Patel, TP; Meaney, DF; Bass, CRD; Morrison, B

Published Date

  • April 2016

Published In

Volume / Issue

  • 33 / 7

Start / End Page

  • 652 - 661

PubMed ID

  • 26414012

Pubmed Central ID

  • PMC5583564

Electronic International Standard Serial Number (EISSN)

  • 1557-9042

International Standard Serial Number (ISSN)

  • 0897-7151

Digital Object Identifier (DOI)

  • 10.1089/neu.2015.4045

Language

  • eng