Abstract:

To compare the various indexes of mouse models of acute lung injury (ALI) established by exposed and   non-exposed intratracheal instillations in order to confirm which method was more suitable. Methods Forty-five male mice were randomly divided into control group,non-exposed group and exposed group.There were fifteen mice in each group.The mice in both non-exposed and exposed groups were instilled with lipopolysaccaride(LPS) to establish ALI models by  non-exposed and exposed intratracheal instillations,respectively. The detection of  biochemical indexes  in bronchoalveolar lavage fluid (BALF),differential cell counting in BALF,lung wet/dry  weight (W/D) ratio,and  pathomorphological observation of lung tissue were performed 24 h after intratracheal instillation.Results The success rate in establishing the mouse ALI model  in exposed group (100%) was higher than that in non-exposed group (86.7%). The total protein concentration in BALF,the alkaline phosphatase(ALP) and lactate dehydrogenase(LDH) activities,the amount of neutrophils in BALF,and lung W/D  ratio were significantly increased in non-exposed and exposed groups compared with control group (P<0.05).The total protein concentration in BALF,the ALP and LDH activities,the amount of neutrophils in BALF and lung W/D ratio in exposed group were significantly higher  than those in non-exposed group (P<0.05).The pathological changes in non-exposed group were characterized by pulmonary interstitial edema,but the exudative pulmonary edema was shown in exposed group.Conclusion The exposed intratracheal instillation is proved to be more suitable to establish the mouse model of ALI.

Key words: intratracheal instillation;acute lung injury;lipopolysaccharide;mice