1.Northwestern Polytechnical University;2..Department of military traffic injury prevention and control, Institute of field surgery, Army characteristic medical center, Chinese people''s Liberation Army
目的 建立激波管对C57BL/6鼠侧卧身位爆炸冲击实验模型，探究24 h内冲击波对C57BL/6小鼠心、肺、脑组织中巨噬细胞/小胶质细胞的力学损伤变化规律，明确组织巨噬细胞/小胶质细胞对爆炸冲击的力学生物学响应。方法 使用激波管对C57BL/6小鼠加载冲击损伤。首先在冲击后的不同时间点测量小鼠体重变化，并在麻醉后解剖取心脏、肺以及全脑组织样本。对组织样本进行病理切片HE染色检测结构损伤；采用TUNEL染色方法标记并统计各组织中死亡细胞比例，使用anti-CD11b、anti-F4/80和anti-Iba1抗体对组织中的巨噬细胞或小胶质细胞进行荧光染色标记，分析冲击加载后机体巨噬细胞/小胶质细胞的力学生物学响应变化规律。结果 激波管对小鼠侧身位加载超压179 KPa的冲击波，小鼠致死率为3.33%。与正常对照组相比，实验组小鼠在加载冲击后24 h内体重显著性下降（P<0.05）；病理切片显示冲击后肺组织血管破裂，并伴随肺泡蛋白质沉积症、肺大疱等病症；荧光染色表明肺组织在24 h内巨噬细胞大量被募集活化，清理死亡细胞比例在24 h回弹到正常水平；心脏对冲击具有较强耐受性，大血管附近出现了巨噬细胞的大量聚集活化；脑部由于冲击姿态影响表现出小胶质细胞单侧聚集现象，主要为灰白质交界处出现长时间的炎症和较高死亡细胞比例。结论 建立了小鼠侧卧身位爆炸冲击模型，在24 h内，巨噬细胞（小胶质细胞）在受到冲击作用后可以迅速募集至损伤部位，介导强烈的免疫应激，并可能参与免疫反应引发二次长期炎症损伤。研究结果为原发性冲击损伤的伤情评价提供量效关系和组织损伤差异性等实验依据。
Objective To establish a blast injury experimental model using a shock tube at the side lying position of C57BL/6 mice, investigate the biomechanical responses of macrophages/microglia cells in heart, lung and brain tissue to mechanical damage by shock wave within 24 hours. Methods Shock tube was employed to generate a shock wave to C57BL/6 mice. Firstly, the weight changes of mice were measured at different time points after the shock. Then the cardiac, pulmonary and whole brain tissue samples were dissected after anesthesia. Pathological sections were stained with HE staining to detect structural damage; the TUNEL staining method was used to mark and count the proportion of dead cells in each tissue. Microglial cells were labeled with fluorescent antibody, while the responses and changes of macrophages/microglia after shock loading were analyzed. Results The shock tube exerted an overpressure shock wave of 179 KPa on the side of the mouse, and the lethal rate of the mouse was 3.33%. Compared with the normal control group, the mice in the experimental group had a significant weight loss within 24 hours after loading shock (P<0.05). Pathological sections showed rupture of lung tissue after shock, accompanied by alveolar protein deposition, pulmonary bulla and other diseases. Fluorescence staining showed that lung tissue was recruited and activated in a large amount within 24 h. And the proportion of dead cells cleared rebounded to normal level within 24 h. The heart was highly tolerant to shock, and macrophages appeared near the large blood vessels. A large number of aggregation activation. The brain showed unilateral aggregation of microglia due to the impact posture, mainly due to prolonged inflammation and a higher proportion of dead cells at the junction of gray and white matter. Conclusion A blast shock model of the lateral lying position of the mouse was established. Within 24 hours, Macrophages/microglia were recruited quickly to the injury site after being impacted, which mediated strong immune stress, and may participate in the immune response to trigger a second long-term inflammatory injury. The results of the study provide experimental basis for the evaluation of primary impact injury, such as dose-effect relationship and tissue damage difference.