百草枯中毒致大鼠肺纤维化模型中肺组织的PAI-1 mRNA表达

The increased expression of PAI-1 in lung tissue of Paraquat-induced rat pulmonary fibrosis model

目的观察纤溶酶原激活物抑制因-子1(PAI-1)在百草枯致大鼠肺纤维化模型中肺组织的表达情况。方法42只健康成年雌性SD大鼠随机分为对照组和染毒组,分别观察7、14和28 d。染毒组于实验开始一次性百草枯(40mg/kg)灌胃染毒,对照组予以等量生理盐水。取肺组织行病理组织学检查,并采用RT-PCR法测定PAI-1 mRNA的表达。结果百草枯染毒后大鼠肺泡炎、肺纤维化程度积分明显增高;肺组织PAI-1 mRNA表达(7、14、28 d分别为1.30±0.37、2.39±0.17、0.56±0.05)明显高于同期对照组(0.07±0.02),差异有统计学意义(P<0.01)。结论百草枯中毒大鼠肺组织PAI-1 mRNA水平的表达明显上调。

Objective To investigate the dynamic expression of plasminogen activator inhibitor-1 （PAI-1） in the lungs in Paraquat （PQ） -induced Pulmonary Fibrosis. Methods Fourty-two adult healthy female SD rats were randomly divided into control and PQ groups. Each group was divided into three subgroups of seven animals each. The rats in PQ group were treated intragastrically （ig） with PQ （40mg/kg） and the rats in control group were treated with the same volume of saline at the beginning of the experiment. The animals of model and control group were sacrificed and lungs were harvested at either seven, 14 or 28 days respectively. A semiquantitative assay of histological examination was used to determine the severity of alveolitis and fibrosis. RT-PCR was used to detect the mRNA expression of PAI-1. Results Inflammatory cell infiltration and fibrotic scores were more prominent in the model group compared to the control group. Further study showed that PAI-1 mRNA on day seven, 14, 28 （1.30±0.37 vs0.07±0.02, 2.39±0.17 vs0.07±0.02, 0.56±0.05 vs 0.07±0.02） were upregulated as compared with that of the control group. Conclusion The PAI-1 expression in the lung tissue of paraquat-induced pulmonary fibrosis in rats is upregulated.