肥大细胞稳定剂对小鼠百草枯中毒后肺损伤的保护作用

The protective effect of mast cell stabilizer on lung injury induced by paraquat poisoning in mice

目的 建立小鼠百草枯中毒肺损伤模型,探讨肥大细胞稳定剂在百草枯中毒肺损伤中的保护作用.方法 健康清洁级雌性昆明小鼠36只,随机分为对照组(A组)、百草枯中毒模型组(B组)、卡托普利干预组(C组)和色甘酸钠干预组(D组).A组小鼠于实验即刻、0.5h及此后每12 h分别腹腔内注射生理盐水(1 mL),至72 h处死;B、C、D组小鼠腹腔内注射百草枯(30mg/kg)一次性染毒,于染毒后0.5h及此后每12 h腹腔内分别注射生理盐水(1 mL)、卡托普利(10 mg/kg)和色甘酸钠(25 mg/kg)直至72 h处死.观察各时点小鼠中毒症状的改变及肺损伤病理学评分,并比较72 h所取肺组织HE染色、Mason染色、COX-2及TGF-β1免疫组化检测结果.结果 D组小鼠中毒症状较其他染毒组明显减轻,A组小鼠肺组织结构完整,B组小鼠肺组织出现严重的炎症性改变,C、D组小鼠肺组织也出现炎症反应,但较B组明显改善.B组小鼠8、24及72 h肺损伤病理评分呈时间依赖性升高(分:5.50±1.80、9.60±4.30、12.30 ±5.80),各组间比较差异有统计学意义(P均<0.05);B、C、D组72 h肺损伤病理评分均显著高于A组(分:12.30±5.80、10.78±4.56、6.35 ±4.71 vs.4.25 ±1.32,P均<0.01),C、D组低于B组(P均<0.05);D组低于C组(P<0.05);B、C、D组72 h蓝染密度均高于A组(8.64±6.53、6.28±5.42、5.53 ±4.26 vs.1,P均<0.01),C、D组低于B组(P均<0.05);D组低于C组(P<0.05);B、C、D组72 h肺组织内COX-2表达明显高于A组(5.34±2.81、4.78 ±2.56、3.35±2.71 vs.1,P均<0.01),C、D组低于B组(P均<0.05),D组低于C组(P<0.05);B、C、D组72 h肺组织内TGF-β1表达明显高于A组(5.76 ±2.12、4.65 ±1.97、2.76±0.89 vs.1,P均<0.01),C、D组低于B组(P均<0.05),D组低于C组(P<0.05).结论 肥大细胞稳定剂对小鼠百草枯中毒肺损伤有保护作用,可能与减少百草枯中毒小鼠肺组织炎性细胞浸润及降低肺纤维化程度有关.

Objective To establish the model of lung injury induced by paraquat in mice and to explore the protective effect of mast cell stabilizer on lung injury induced by paraquat.Methods Thirty_six healthy Kunming mice were randomly divided into control group(group A),paraquat model group(group B),captopril intervention group(group C)and cromolyn sodium intervention group(group D).Mice in group A were injected intraperitoneally with 1 mL normal saline immediately,0.5 h and every 12 h thereafter,and sacrificed at 72 h;Mice in groups B,C and D were injected intraperitoneally with paraquat(30 mg/kg)for one-time exposure,after 0.5 h of exposure and every 12 h thereafter,mice in group B were injected intraperitoneally with 1 mL normal saline until they were sacrificed,mice in group C were injected intraperitoneally with captopril(10 mg/kg)until they were sacrificed,mice in group D were injected intraperitoneally with cromolyn sodium(25 mg/kg)until they were was sacrificed.The poisoning symptoms of the mice were observed after administration,and the HE staining,Mason staining,COX-2 and TGF-β1 immunohistochemistry were compared.Results The poisoning symptoms of mice in group D was significantly reduced compared with other three groups.The lung tissues of mice in group A was intact,while which in group B showed severe inflammatory changes.The lung tissue of mice in group C and D also showed inflammatory reaction,but which were significantly improved compared with group B.The pathological scores of lung injury in group B at 8 h,24 h and 72 h showed time-dependent increase[(5.50±1.80),(9.60±4.30),(12.30土5.80)],and the differences between each two groups were significant(all P < 0.05).Pathological scores of lung injury in group B,group C and group D for 72 h were significantly higher than those in group A(12.30±5.80,10.78±4.56,6.35±4.71 vs.4.25±1.32,all P<0.01),while which in group C and D were lower than which in group B(all P<0.05),also which in group C was higher than that of group D(P<0.05).The blue-staining densities of group B,group C and group D for 72 h after Masson staining were higher than that of group A(8.64±6.53,6.28±5.42,5.53±4.26 vs.1,P<0.01),while that of group C and D were lower than that of group B(all P<0.05),also which in group C was higher than that of group D(P<0.05).COX-2 expression in lung tissues of group B,group C and group D for 72 h were significantly higher than that of group A(5.34±2.81,4.78±2.56,3.35±2.71 vs.1,all P<0.01),but which in group C and group D were lower than that of group B(all P<0.05),also which in group C was higher than that of group D(P<0.05).TGF-β1 expression in lung tissues of group B,group C and group D for 72 h were significantly higher than that of group A(5.76±2.12、4.65±1.97、2.76±0.89 vs.1,all P<0.01),but which in group C and group D were lower than that of group B(all P<0.05),also which in group C was higher than that of group D(P<0.05).Conclusion Mast cell stabilizer has protective effect on paraquat lung injury in mice,which may be related to reducing the infiltration of inflammatory cells and the degree of pulmonary fibrosis in lung tissue of mice.