An acute lung injury model caused by seawater aspiration in rats

Objective:To establish an acute lung injury model by seawater aspiration in rats.Methods: Twenty-four rats were randomly allocated into 2 groups: control group(n=9) and model group(n=15).The acute lung injury model was established in rats by aspirating 2 ml seawater/kg body weight after 9-10 seconds of breath occlusion.The aspiration was repeated by the same means 2 min later.Rats in control group aspirated no seawater.Arterial blood gases and respiratory rates were observed before aspiration and 10 min,30 min,1 h,2 h and 4 h after aspiration.The survival times of animal were also recorded.The rats were sacrificed 4 h after aspiration;the lung index,total protein(TP) contents,white blood cell(WBC) count in bronchoalveolar lavage fluid(BALF),and the pulmonary histopathology were observed.Results: Compared with control group,model group had a significantly increased respiratory rate and a decreased PaO_(2)(P0.05),which subsequently rose again and remained at a lower level.The model group also had a markedly increased lung index,TP contents and WBC counts((P)(0.05).) Obvious edema,alveolar atrophy and inflammatory infiltration were found in model rats.Conclusion: An acute lung injury model by seawater aspiration has been successfuly established.