Objective:To investigate the mechanism and the rapeutic effect of Reduning injection(RDN) on acute lung injury(ALI) in rats. Method: Sixty rats were randomly divided into six groups

normal group

model group

positive control group (dexamethasone

2 mg · kg-1)

high-

medium-

low-dose RDN groups (10.16

5.08

2.54 g · kg-1).The ALI rats was induced by ipopolysaccharide(LPS) except for rats in normal group. The effects of wet /dry weighto (W/D) ratio in lung

the total protein contents of bronchoalveolar lavage fluid (BALF)

superoxide dismutase (SOD)

malondialdehyde (MDA)

myeloperoxidase (MPO) in serum and interleukin(IL) -1β

tumor necrosis factor (TNF) -α

IL-10 in lung homogenate were observed. Result: The W/D ratio

BALF

the content of MDA

IL-1β

TNF-α

IL-10 were decreased

the activity of MPO was inhibited and the activity of SOD was activated in model group. The above indexes were all improved in all dosage of RDN groups(P<0.01

P<0.05). Conclusion: RDN can improve the pathological changes of lung tissueand reduce the oxidative stress reaction of ALI process. Its mechanism may be achieved by reducing the inflammatory factor in vivo.