急性百草枯中毒大鼠肺组织中MMP-2和MMP-9表达的变化研究

STUDY ON EXPRESSION OF MATRIX METALLOPROTEINASE-2 AND MATRIX METALLOPROTEINASE-9 IN LUNG TISSUES OF RATS OF ACUATE PARAQUAT POISONING

[目的]观察急性百草枯(PQ)中毒大鼠肺组织中基质金属蛋白酶(MMP-2和MMP-9)的表达变化,探讨其在百草枯中毒致肺纤维化中的表达及意义。[方法]SD大鼠50只,随机分为染毒组和对照组,染毒组用PQ按50mg/kg灌胃染毒,对照组代以等剂量生理盐水灌胃。灌胃后1,3,7,14和28d分离和提取肺间质成纤维细胞,应用免疫细胞化学和逆转录多聚酶链式反应(RT-PCR)方法,观察其MMP-2,MMP-9蛋白及其 mRNA的动态变化。[结果]①PQ灌胃后1d成纤维细胞MMP-2表达增高,7d达高峰,为对照组的3.187倍(t=23.667,P﹤0.001);MMP-9在PQ灌胃作用后1d表达增高,7d达对照组的3.503倍(t=11.399,P﹤0.001);②MMP-2 mRNA和MMP-9 mRNA的转录从PQ灌胃后1d就开始升高。[结论]PQ灌胃后,肺间质成纤维细胞上调MMP-2和MMP-9的表达,损伤肺泡基底膜,启动肺纤维化的发生。

[Objective] To investigate the changes of expression of matrix metalloproteinase in hmg tissues of rats with acute paraquat （PQ） poisoning. [Methods] A total of 50 SD rats were randomly divided into control group and poisoned group. Intra-gastrie adnfinistrations with PQ in dose of 50 mg/kg or nornral saline solution in the same dose were given the poisoned group and the control group respectively. On the days of 1, 3, 7, 14 and 28 alter exposure, the expressions of MMP-2 and MMp-2mRNA, MMP-9 and MMP-gmRNA in lung tissues were evaluated by RT-PCR. [Results] ① The expressions of both MMP-2 and MMP-9 in fibroblasts increased on the first day after poisioning and reached the peak on the seventh day. And the expression of MMP-2 was 3.187 times as many as that of the control group （t = 23.667, P 〈 0.001）, while the expression of MMP-9 was 3.503 times as many as that of the control group （t = 11.399, P 〈 0.001） .② The expressions of MMP-2mRNA mid MMP-9mRNA were enhanced in fibroblasts at 24 h ,after poisioning. [ Gonclusions] The expressions of MMP-2 and MMP-9 in fibroblasts are up-regulated in pulmonary interstitial fibrosis model.