糖皮质激素对急性肺栓塞后肺组织内硫氰酸生成酶表达的影响  

Effects of glucocorticosteroid on expression of rhodanase in lung tissues after acute PE

作　　者：李圣青[1] 任新玲[1] 刘阿茹[1] 远帝新宇 简文[1] 欧阳海峰[1] 赵峰[1] 

机构地区：[1]第四军医大学西京医院呼吸科,陕西西安710032

出　　处：《中国现代医学杂志》2008年第3期293-297,301,共6页China Journal of Modern Medicine

摘　　要：目的研究糖皮质激素对大鼠急性肺栓塞后肺组织内硫氰酸生成酶(rhodanase,Rho)表达的影响。方法建立大鼠急性肺栓塞模型,分别在急性肺栓塞后1、8、24和48h开胸取出肺组织。常规提取肺组织的总RNA和总蛋白,以正常组为对照,采取半定量RT-PCR和westernblot方法研究Rho在mRNA水平和蛋白水平的表达变化;采用免疫组织化学的方法检测大鼠肺组织中Rho在肺栓塞前后表达的变化及其组织分布情况。在大鼠急性肺栓塞后48h,采用RT-PCR和western blot方法观察地塞米松(dexamethasone,DEX)对Rho蛋白表达的影响。分离培养原代大鼠气道上皮细胞,在培养液中加入50ng/mL的共刺激因子IL-1β,TNF-α和IFN-γ,采用半定量RT-PCR,westernblot和免疫荧光染色的方法观察1μM的DEX对上皮细胞Rho表达的影响,采用ELISA方法检测上皮细胞IL-8和GM-CSF的表达。结果大鼠急性肺栓塞后,Rho的mRNA水平和蛋白水平均逐渐下降,免疫组化研究表明Rho主要分布在支气管粘膜上皮细胞,在急性肺栓塞后表达显著下降。DEX可显著提高Rho的肺内表达。大鼠气道上皮细胞在共刺激因子的作用下IL-8和GM-CSF的表达显著升高,DEX可明显抑制IL-8和GM-CSF的表达,但是Rho的表达显著升高。结论大鼠急性肺栓塞后肺组织内Rho的表达明显下降,糖皮质激素可升高Rho的表达。离体实验证明糖皮质激素是通过抑制上皮细胞的炎症反应来提高Rho的表达。[Objective] To study the effects of glucocorticosteroid on the expression of rhodanase （Rho） in the lung tissues of a rat acute pulmonary embolism （PE） model [Methods] A rat acute PE model was constructed. The samples of lung tissues were collected at different time points of 1 h, 8 h, 24 h and 48 h. The normal rats were used as controls. The mRNA level changes of Rho were identified by semi-quantitative RT-PCR, and the protein level changes were identified by Western blot methods. The immunohistochemical method was employed to study the distribution and expression changes of Rho in the lung tissues after acute PE. The methods of semi-quantitative RTPCR and Western blot were employed to study the effects of dexamethasone（DEX） on the expression of Rho at 48 h after acute PE. Primary rat airway epithelial cells were isolated and cultured in the presence of 50 ng/mL cytomix, IL-1β, TNF-α and IFN-γ. The effects of 1μM DEX on the expression of Rho were studied by the methods of semiquantitative RT-PCR, Western blot and immunofluorescent staining. The expression of IL-8 and GM-CSF in epithelial cells was determined by ELISA method. [Results] The mRNA and protein levels of Rho decreased in the lung tissues after acute PE. The immunohistochemical study indicated that Rho was mainly expressed in the bronchial epithelial cells, and its expression was down-regulated after acute PE. DEX could obviously increase the expression of Rho in the lung tissues. The expression of IL-8 and GM-CSF in epithelial cells stimulated by the cytomix was up-regulated obviously, but DEX could inhibit their expression and up-regulate the expression of Rho. [Conclusion] The expression of Rho is down-regulated in the lung tisues after acute PE, but can be up-regulated by DEX. Glucocordcosteroid can greatly increase the expression of Rho in epithelial cells in vitro by playing its anti-inflammatiory role.

关 键 词：急性肺栓塞 大鼠气道上皮细胞 硫氰酸生成酶 糖皮质激素 

分 类 号：R563.5[医药卫生—呼吸系统]