Simulated blast overpressure induces specific astrocyte injury in an ex vivo brain slice model

Exposure to explosive blasts can produce functional debilitation in the absence of brain pathology detectable at the scale of current diagnostic imaging. Transient (ms) overpressure components of the primary blast wave are considered to be potentially damaging to the brain. Astrocytes participate in neuronal metabolic maintenance, blood–brain barrier, regulation of homeostatic environment, and tissue remodeling. Damage to astrocytes via direct physical forces has the potential to disrupt local and global functioning of neuronal tissue. Using an ex vivo brain slice model, we tested the hypothesis that viable astrocytes within the slice could be injured simply by transit of a single blast wave consisting of overpressure alone. A polymer split Hopkinson pressure bar (PSHPB) system was adapted to impart a single positive pressure transient with a comparable magnitude to those that might be present inside the head. A custom built test chamber housing the brain tissue slice incorporated revis...暴露于爆炸冲击波环境中时，即便当前诊断成像尺度下无法检测到脑部病理改变，也可引发脑部功能性损伤。原发性冲击波的毫秒级瞬时超压分量，被认为具有潜在的脑损伤风险。星形胶质细胞（Astrocytes）参与神经元代谢维持、血脑屏障（blood–brain barrier）稳态环境调控以及组织重塑等生理过程。直接物理作用导致的星形胶质细胞损伤，有可能破坏神经元组织的局部与整体功能。本研究采用离体（ex vivo）脑片模型，验证了如下假说：仅由超压构成的单次冲击波传导，即可造成脑片内存活星形胶质细胞的损伤。我们改造了聚合物分离式霍普金森压杆（Polymer Split Hopkinson Pressure Bar, PSHPB）系统，以施加单次正压瞬时脉冲，其强度可与颅脑内部可能出现的冲击波超压相匹配。我们搭建了定制化测试舱以容纳脑片组织，该舱体集成了经改进的……