中性粒细胞在高浓度氧诱发急性肺损伤中的作用

Effect of neutrophil on hyperoxia-induced acute lung injury

目的:测定鼠支气管肺泡清洗液中细胞成分,阐明高浓度氧诱发急性肺损伤的发生机制。方法:20只雄性6周龄[(226±53.6)g]Wistar鼠被分为3组:(1)对照组(空气中饲养,n=6)。(2)实验组1(暴露在90%～95%氧气中24～48h,n=7)。(3)实验组2(暴露在90%～95%氧气中72h,n=7)。实验中动物可自由进食和水。结果:与对照组相比,实验组2的支气管肺泡清洗液中总细胞数减少[(3.81±0.35)×105/ml,(2.53±0.77)×105/ml];巨噬细胞数减少[(3.80±0.36)×105/ml,(2.09±0.59)×105/ml];而中性粒细胞计数明显增多[0,(43.56±42.63)×103/ml]。实验组2的动物都出现双侧胸水。结论:中性粒细胞动员并进入肺组织是高浓度氧诱发急性肺损伤的明显特征,损伤的发生与暴露时间有关。提示早期抑制中性粒细胞进入肺组织是治疗高浓度氧诱发急性肺损伤的重要途径。

Objective： To clarify mechanism of acute lung injury （ALI） caused by high concentration oxygen exposure by measuring the cell counts in bronchoalveolar lavage fluid（BALF） in the rats. Methods： Young male Wistar rats [（226±53.6 ）g] were divided into three groups： （1）control group（exposed to room air,n=6）;（2）experiment group 1 （exposed to 90%-95% oxygen for 24-48 h,n=7） ; （3） experiment group 2（exposed to 90%-95% oxygen for 72 h,n=7）. During the exposures,food and water were provided at libitum. Results：Compared to the control group, in group 2 total cell counts and macrophage in BALF were lower （P〈0.01）whereas neutrophils higher were （P〈0.01）.All rats in group 2 were noted to have bilateral pleural effusions. Conclusion：The data suggest that the influx of neutrophils into the lung is a histological feature of hyperoxic lung injury and hyperoxic lung injury is related to the duration exposed to the oxygen.Blocking neutrophil influx into lung tissue in the early phase is a effective method to reduce hyperoxic lung injury.