OBJECTIVETo observe the effects of tetrandrine (Tet) on the pulmonary capillary permeability in rats with acute lung injury induced by intravenous injection of lipopolysaccharide (LPS).

METHODSThirty-two healthy male Wistar rats were randomly divided into 4 groups: the model group, the normal group, the Tet prevention group and the Tet treatment group, 8 in each group. All rats except those in the normal group, were established into acute lung injury model by intravenous injection of LPS. Intravenous injection of Tet (20 mg/ kg) were given to the Tet prevention group 30 min before and to the Tet treatment group 30 min after modeling respectively, and equal volume of normal saline was given to the other two groups instead. Arterial blood samples were collected to determine PaO2 and PaCO2 at the time points of immediately after modeling (0 h), 0.5 h, 2 h, 4 h, 6 h. The animals were sacrificed by the end of the experiment, the wet/dry weight ratio of lung (W/ D), neutrophil percentage in bronchoalveolar lavage fluid (BALF), concentration of TNF-a in peripheral blood and BALF by ELISA, and content of malonaldehyde (MDA) in lobus inferior pulmonis homogenate by thio barbituric acid colorimetric method were determined. Pathological change of the upper lobe of lung was examined and lung injury was scored as well.

RESULTSAs compared with that in the model group, the level of PaO2 was higher in Tet prevention group at 0.5 h, 2 h, 4 h, 6 h and in the Tet treatment group at 2 h, 4 h, 6 h (P< 0.05); and the content of TNF-alpha, MDA and neutrophil percentage in BALF, as well as W/D and lung injury score were lower in the Tet prevention group and the Tet treatment group (P <0.05). Pathological changes of lung in the two Tet groups were all better than those in the model group.

CONCLUSIONEarly intervention with tetrandrine shows a protectiv effect on rats against acute lung injury induced by intravenous injection of LPS.