Objective:To discuss the effect of curcumin pretreatment on rats with lung ischemia reperfusion injury.Methods:Divided 48 healthy adult male SD rats into sham operation group(group S),ischemia reperfusion group(group IR),low-concentration curcumin group(group C50)and high-concentration group(group C200)randomly,12 rats in each group.Group C50 and group C200 receiveddisposablel abdominal injection of curcumin(50 mg/kg and 200mg/kg respectively)2 h before anesthesia,occluding left pulmonary hilus for 60 min and reperfusing for 180 min.Group S received abdominal injection of equivalent saline 2 h before anesthesia,no occlusion of the left pulmonary hilus after opening chest,and was put aside for 240 min.Group IR received abdominal injection of equivalent saline 2 h before anesthesia,occluding leftpulmonary hilus for 60 min and reperfusing for 180 min.Before ischemia and in the 60th,120th and 180th min of reperfusion,collected the blood of right carotid artery to conduct a blood gas analysis,and calculated the respiratory index(RI).In the end of reperfusion,the rats were sacrificed for collecting the pulmonary tissue.Observed the pathological changes of the pulmonary tissue,measured wet-dry weight ratio(W/D),detected the content of superoxide dismutase(SOD)and malondialdehyde(MDA).Results:Comparing with that before ischemia,RI of the group IR in each time point of reperfusion was significantly increased(P< 0.05).Comparing with that of group S,RI of the group IR in each time point of reperfusion was significantly increased,the content of MDA,W/D and scores of pulmonary injury were higher,while the activation of SOD was lower,differences being significant(P< 0.05).Comparing with that of group IR,RI of the group C50 and group C200 in each time point of reperfusion wassignificantly decreased,the content of MDA,W/D and scores of pulmonary injury were lower,while the activation of SOD washigher,differences being significant(P< 0.05).Comparing with that of group C50,RI of the group C200 in each time point of reperfusion was significantly decreased,the concentration of MDA,W/D and scores of pulmonary injury were lower,while the activation of SOD was higher,differences being significant(P< 0.05).Conclusion:Curcumin pretreatment can release lung ischemia reperfusion injury in a dose-dependent manner,and the mechanism may be relevant with its curcumin of releasing pulmonary edema,reducing the formation of oxidation products and enhancing the function of clearing oxygen free radicals.