Objective To investigate the effects of Cromolyn Sodium on the lung injury caused by intestinal ischemia reperfusion in rats.Methods 32 SD rats were randomly divided into four groups: sham group(group A),model group(group B),high dosage group,(treated with Cromolyn Sodium 50 mg/kg,group C);low dosage group(treated with Cromolyn Sodium 25 mg/·kg/,group D).Intestinal damage was induced by clamping the superior mesenteric artery for 45 min and reperfusion for 60 min.Cromolyn Sodium was administrated via intaperitoneal at 15 min before reperfusion.At the end of study,the lungs were immediately removed for determination of lung water content [(wet weight-dry weight) / wet weight x 100%],lung MDA contents and SOD activity,lung permeability index(BALE protein concentration / serum protein concentration) and microscopic examination.Results ① The score of lung injury in group B was higher than the other groups(P<0.01),high dosage Cromolyn Sodium provided better protective effects than low dosage(P<0.05).② Mast cell number and histamine concentration in pulmonary were no significant difference among four groups.③ Lung water content,lung permeability index increased significantly in group B compared group A(P<0.05),Cromolyn Sodium significantly prevented the above changes(P<0.05).④ MDA content was significant increased,and SOD activity was significant decreased in group B(P<0.01).Cromolyn Sodium attenuated the increase in MDA content and the decrease in SOD activity(P<0.05).There was positive correlation between the lung injury score and MDA content,and there was negative correlation between the lung injury score and the SOD activity in the four groups(P<0.01).Conclusion Cromolyn Sodium can protect lung injury caused by intestinal ischemia reperfusion by nonspecific antioxidant properties,mast cells in pulmonary have little effect on the lung injury caused by intestinal ischemia reperfusion. Objective To investigate the effects of Cromolyn Sodium on the lung injury caused by intestinal ischemia reperfusion in rats. Methods 32 SD rats were differentiated into four groups: sham group (group A), model group (group B), high dosage group, ( treated with Cromolyn Sodium 50 mg / kg, group C); low dosage group (treated with Cromolyn Sodium 25 mg / kg / group D) .Intestinal damage was induced by clamping the superior mesenteric artery for 45 min and reperfusion for 60 min .Cromolyn Sodium was administered via intaperitoneal at 15 min before reperfusion. At the end of study, the lungs were immediately removed for determination of lung water content [(wet weight-dry weight) / wet weight x 100%], lung MDA contents and Results: ① The score of lung injury in group B was higher than the other groups (P <0.01), high dosage of Cromolyn Sodium provided better protective effects than low do sage (P <0.05) .②Mast cell number and histamine concentration in pulmonary were no significant difference among four groups. ③ Lung water content, lung permeability index increased significantly in group B compared group A (P <0.05), Cromolyn (P <0.05) .④ MDA content was significantly increased, and SOD activity was significantly decreased in group B (P <0.01) .Cromolyn Sodium attenuated the increase in MDA content and the decrease in SOD activity There was positive correlation between the lung injury score and MDA content, and there was negative correlation between the lung injury score and the SOD activity in the four groups (P <0.01) .Conclusion Cromolyn Sodium can protect lung injury caused by intestinal ischemia reperfusion by nonspecific antioxidant properties, mast cells in pulmonary have little effect on the lung injury caused by intestinal ischemia reperfusion.