Abstract: To establish acute lung injury model, New Zealand White rabbits were divided into model group (n=13) and control group (normal group, n=5). The animals in the model group were injected intravenously with Escherichia coli lipopolvsaccharide (LPS) 0.1mg/kg (pretreated with one tenth of the total dose 12h before). Gas change, lung mechanics, blood pressure and pulse were monitored under mechanical ventilation. The lung injury was observed 8h after the second injection of LPS. The measurement values for PaO₂/FiO₂ alveolar - arterial O₂ gradient (A -aD0₂) , intrapulmonary shunting (Qs/Qt)，Cdyn and Rrs showed that the pulmonary function in the model group was significantly worse than that before the second injection of LPS and that in the control group (P＜0.01). In the model group, PaO₂/FiO₂ was below 40kPa, atelectasis, edema, hemorrage ancl inflammatory infiltrates were also seen in the lung sections 14h after the 2nd injection of LPS，white blood cell count and total protein (TP) content were significantly increased in BALF，ancl wet/dry weight ratio of the lung was also significantly increased. It is concluded that acute lung injury model has been established within 8～14h by injection of endotoxin intravenously based on impaired gas change, lung mechanics, ancl increased blood cell count and TP content in BALF.

Key words: Acute lung injury, Endotoxin, Rabbit, Model