Effect of captopril on serum TNF-α level in acute lung injury rats induced by HCL

ABSTRACTObjectiveTo observe the effect of captopril on the tumor necrosis factor-α (TNF-α) level and arterial blood gases in acute lung injury (ALI) induced by HCL in rats, and to analyze its protective mechanism.MethodsFifty Wistar rats were selected and randomly divided into three groups, with 20 rats in Group I and II, respectively and 10 animals in Group III. ALI model was constructed by intratracheal injection of diluted hydrochloric acid (pH=1.25, 1.2 mL/kg). Group I rats received not any treatment after construction of ALI model. Group II rats were treated with captopril (5 mg/kg, i.p.) 5 min after induction of ALI. Group III served as normal control without any treatment. Ninety minutes after construction of ALI model, all the rats were sacrificed. Blood was withdrawn for detection of TNF-α level and arterial blood gases index. And lung tissue slices of the three groups were prepared for observation of pathologic histology changes.ResultsTNF-α level in serum of Group I and II rats was significantly higher than that in Group III (P<0.05), while TNF-α level in serum of Group II was significantly lower in Group I (P<0.05). PaCO2 level was significantly higher (P<0.05), while PaO2 was significantly lower (P<0.05) in Group I and II rats than those in Group III. PaCO2 was significantly lower (P<0.05) and PaO2 was significantly higher (P