Experimental study on the protective effect of Tanreqing injection on endotoxin-induced acute lung injury in mice

OBJECTIVE To explore the protective effect and mechanism of Tanreqing injection(TRQ)on endotoxin(LPS)-induced acute lung injury in mice.METHODS A total of 30 healthy and clean ICR mice were randomly divided into normal saline groups(n=10),ALI(n=10)and TRQ-treated ALI groups(n=10).A mice model of normal atmospheric temperature was established in the acute lung injury and TRQ-treated ALI groups,while normal saline group was simulated without use of LPS and intratracheal instillation with saline(2 ml·kg-1)instead of;the mice in TRQ-treated ALI group were administered with tail vein injection of Tanreqing(4 ml·kg-1)immediately after the model was established,while the other two groups received the same volume of normal saline(0.9%).Arterial and lung tissue samples were collected from10 mice in each group at 6 h after the model was established.The content of serum NO and arterial blood gas levels were measured;lung tissue apoptosis was evaluated,and expression of myocardial Caspase-3 was measured.RESULTS Compared with the NS group,in ALI group the lung index increased(P0.05);the serum NO levels increased significantly(P0.01);PaO2 declined significantly(P0.01).Lung tissue damage was apparent,Caspase-3 expression positive rate was significantly increased(P0.01).Compared with ALI group,the TRQ group decreased lung index(P0.05);the serum NO levels decreased significantly(P 0.01);PaO2 increased significantly(P0.05).The degree of lung tissue injury in the TRQ group was significantly reduced than that in ALI group,and Caspase-3 expression positive rate was significantly lower(P0.01).CONCLUSION NO in the pathogenesis of ALI induced by LPS plays an important role in the process,TRQ exerts a protective effect on the lung tissue of mice with acute lung injury by lowering serum NO content,and reducing the Caspase-3 protein expression.