巨噬细胞在急性肺损伤中的作用

目的 通过观察急性肺损伤中炎细胞的变化规律。阐明炎细胞在急性肺损伤中的作用。方法 采用20%Ⅲ度体表烧伤复合一次性腹腔内毒素（1mg/kg)注射为实验动物模型。并分别以单纯烧伤，单纯内毒素注射，生理盐水注射为对照组，观察伤后肺组织的病理变化，支气管肺泡灌洗液（BALF）中的细胞总数及中性粒细胞（PMN）分类计数。结果 单烧组和单注组BALF细胞总数明显高于正常对照组，主要是巨噬细胞（Mφ）增加，而烧注组BALF细胞总数除1.5h外无明显升高，1.5h时PMN比例却明显增加，烧注组肺病理改变比单烧组，单烧组明显加重，以伤后1.5h最为显著，结论 PMN是内毒素血症急性肺损伤的主要效应细胞，而Mφ则对急性肺损伤可能有某种保护作用。

Effect of macrophages in acute lung injury

Objective In order to explore the change and the role of inflammation cells in acute lung injury, we induced the experimental animal model of the acute lung injury by burns injury combined with endotoxemia injection.Methods The rat subjected to third degree thermal injury of 20% total body surface area(TBSA), combined with injection of endotoxin(1 mg/kg B.W)intraperitoneally was used as the experimental animal model in the present research. Simple burn(SB) injury group, simple endotoxin(SE) injection group and normal saline group were used as control groups respectively. The histological changes of rats lung, the white blood cell count and the neutrophil differential in the bronchoalreolar lavage fluid(BALF) were investigated. Results In the BE group, the neutrophil differential count in BALF was significantly increased at 1.5 h postinjury, with the seriously lung pathological injury; In the SB group and the SE group, the white blood cell count was markly increased at each time point postinjury, with the mild lung injury.Conclusion PMN is the main cells of the acute lung injury, but macrophages play the role of protecting effection.