自由场爆炸冲击波对大鼠的损伤效应及其神经行为的影响

Effects of free sound field blast shock waves on damage effect and neuro behavior in rats

目的探讨自由场爆炸冲击波对大鼠的损伤效应及其神经行为的影响,为弹药生物毁伤效应的评估及防护、救治提供实验依据。方法健康成年SD大鼠90只,按照弹药类型和布放距离(18、20、25、30 m)随机分为三硝基甲苯爆炸(TNT)组(n=40)、温压(TB)爆炸组(n=40)与对照组(n=10)。采用TNT和TB装药在自由场爆炸,布放压力感受器测量距爆源不同距离的冲击波参数,通过大体解剖、组织病理检查及校正损伤严重程度指数(ASII)进行大鼠伤情判定,旷场和Morris水迷宫实验评估大鼠的神经行为学变化。结果TNT爆炸组和TB爆炸组爆炸冲击波峰压、冲量均随距爆心距离延长而不断降低;TNT爆炸组18 m、20 m大鼠出现死亡(3/10、1/10),TB爆炸组大鼠全部存活,死亡大鼠表现为以肺冲击伤为主的复合伤;爆炸后24 h HE染色可见肺泡间隔增宽,红细胞和炎性细胞浸润,脑组织未发现明显异常病理改变;TNT爆炸组和TB爆炸组大鼠ASII评分与冲击波峰压明显相关(r=0.81、0.70,P<0.05);TNT爆炸组不同距离大鼠总活动时间、总活动距离较对照组缩短,但差异无统计学意义(P>0.05)。TNT爆炸组20 m大鼠中央区域活动时间、中央区域活动距离较对照组缩短(P<0.05);TNT爆炸组18 m和TB爆炸组20 m大鼠逃逸潜伏期较对照组缩短,平台穿越次数较对照组增多,目标象限停留时间较对照组延长(P<0.05)。结论自由场弹药爆炸冲击波对大鼠的损伤程度与爆炸距离有关,呈冲击波峰压及冲量依赖性;爆炸冲击波可影响大鼠的行为和空间记忆能力。

Objective To observe the effects of free sound field blast shock waves on damage effect and neuro behavior in rats,so as to provide the experimental basis for evaluating the biological damage effect of ammunition and proposing the related protective and treatment measures.Methods Ninety SD rats were randomly divided into trinitrotoluene(TNT)explosion group(n=40),thermobaric(TB)explosion group(n=40)and control group(n=10)according to ammunition type and laying distance(18,20,25,30 m).TNT and TB ammunition were detonated in the free field and the shock wave parameters at different distances from the explosion source were measured by pressure transducers.The degree index of injury of rats was evaluated by grass anatomy,histopathology and adjusted severity of injury index(ASII)scoring system.Behavioral changes of the rats were evaluated with Open field test and Morris water maze test.Results The peak pressure and impulse of explosion shock wave decreased continuously with increasing distance from the explosion center in TNT explosion group and TB explosion group.The rats in TNT explosion group died at 18 m(3/10)and 20 m(1/10),while all rats in TB explosion group survived.The dead rats showed a combined lung blast injury.HE staining showed widened alveolar septa and infiltration of red blood cells and inflammatory cells,and no obvious pathological changes were found in brain tissue 24 hours after explosion.Significant correlation existed between ASII score and shock wave peak pressure in TNT explosion groups(r=0.81,P<0.05)and TB explosion groups(r=0.70,P<0.05).The parameters of total move time and total move distance of rats in different positions were shorter in TNT explosion group than in control group,but without statistical significance(P>0.05).Compared with the control group,the move time and distance of rat in 20 m central region were shorter in TNT explosion group(P<0.05).Compared with the control group,the escape latency of rats in TNT explosion group 18 m and TB explosion group 20 m was shortened,the platform crossing time increased,and the residence time in target quadrant prolonged(P<0.05).Conclusions The injury degree of free-field blast shock wave in rats is related to the distance to explosion center with a shock wave peak pressure and impulse dependence.The blast shock wave can affect the behavior and spatial memory ability of rats.