中文摘要：

目的：研究滴注空气对脂多糖（LPS）诱导的小鼠急性肺损伤（ALI）模型的影响，为建立更加有效的气管滴注方法提供依据。方法：45只健康雄性C57BL／6J小鼠随机分为对照组、LPS组和LPS＋空气组，每组15只。以LPS作为刺激物，LPS组和LPS＋空气组小鼠采用暴露式气管滴注方法建立ALI模型，LPS＋空气组小鼠行气管滴注前1mL注射器内预先吸入100μL空气，对照组小鼠不进行任何处理。气管滴注后24h进行支气管肺泡灌洗液（BALF）中生化指标检测、细胞分类计数、肺湿／干重（W／D）比值测定和肺组织形态学观察。结果：与对照组比较，LPS组和LPS＋空气组小鼠BALF中碱性磷酸酶（ALP）和乳酸脱氢酶（LDH）活性、总蛋白浓度、总细胞和中性粒细胞数量以及肺W／D比值显著升高（P〈0．05）；与LPS组比较，LPS＋空气组小鼠BALF中ALP和LDH活性、总蛋白浓度、总细胞和中性粒细胞数量以及肺W／D比值显著升高（P〈0．05）。肺组织学观察，与对照组比较，LPS组和LPS＋空气组小鼠肺组织均有不同程度的液体积聚、中性粒细胞浸润、充血和出血；与LPS组小鼠比较，LPS＋空气组小鼠肺泡腔内积聚了更多富含蛋白的液体、中性粒细胞和红细胞。结论：滴注空气可以用于改进气管滴注方法，建立更加可靠的ALI动物模型。

英文摘要：

Objective To investigate the effect of instilled air on lipopolysaccharide （LPS） -induced mouse model of acute lung injury （ALI） and to provide evidence for establishment of more effective intratracheal instillation. Methods Forty-five male C57BL/6J mice were randomly divided into control group （n= 15）, LPS group （n= 15）, and LPSq-air group （n=15）. The mice in LPS and LPS-t-air groups were instilled with LPS to establish ALI models by exposed intratracheal instillation method. LPS was instilled intratracheally into the lungs of the mice in LPS-t-air group with 1 mL syringe prefilled with 100 μL air and the mice in control group were not treated. The detection of the biochemical indexes in bronchoalveolar lavage fluid （BALF）, cell differential counting in BALF, lung wet/dry weight （W/D） ratio, and the morphological observation of lung tissue were performed 24 h after intratracheal instillation. Results Compared with control group, the activities of alkaline phosphatase （ALP） and lactate dehydrogenase （LDH）, the concentrations of total protein in BALF, the amounts of total cells and neutrophils in BALF, and lung W/D ratios of the mice in LPS and LPSq-air groups were significantly increased （P〈0.05）. Compared with LPS group, the activities of ALP and LDH, the concentration of total protein in BALF, the amounts of total cells and neutrophils in BALF, and lung W/D ratio in LPS＋ air group were significantly increased （P〈0.05）. The histological observation results of lung tissue showed that there were different degrees of fluid accumulation, neutrophils infiltration, congestion and hemorrhage of the mice in LPSq-air and LPS groups compared with control group; there were more protein-rich fluid, neutrophils and erythrocytes accumulated in alveolar spaces of the mice in LPS＋air group compared with LPS group. Conclusien The instilled air can be used to improve the method of intratracheal instillation and establish the more reliable experimental animal model of ALI.