血管内皮生长因子及其受体2与哮喘模型大鼠气道平滑肌细胞增殖关系的研究

CORRELATION OF AIRWAY SMOOTH MUSCLE CELL PROLIFERATION WITH EXPRESSION OF VASCULAR ENDOTHELIAL GROWTH FACTOR AND ITS RECEPTOR 2 IN ASTHMATIC RATS

目的探讨血管内皮生长因子（VEGF）及其受体2（Flk-1）在哮喘大鼠气道平滑肌细胞（ASMC）中表达变化及其对ASMC增殖的影响。方法 SD大鼠18只,随机分为对照组,哮喘模型组和地塞米松干预组各6只,并培养各组气道平滑肌细胞。用免疫组织化学技术检测ASMC增殖细胞核抗原（PCNA）的表达;用RT-PCR及Western blot方法分别检测VEGF和Flk-1mRNA及蛋白质在不同组大鼠ASMC的表达程度。结果（1）哮喘模型组ASMC PCNA表达较对照组和干预组显著增加（P〈0.05）。（2）哮喘模型组ASMC VEGF164,VEGF188mRNA和VEGF205mRNA的表达较对照组和干预组显著增加（P〈0.05或P〈0.01）。（3）哮喘模型组ASMC VEGF及Flk-1蛋白质在大鼠ASMC中的表达较对照组和干预组显著增加（P〈0.05）。直线相关性分析显示,大鼠ASMC PCNA表达与大鼠ASMC中VEGF205,188,164及Flk-1mRNA表达水平呈正相关（r分别为0.79,0.86,0.83,0.68;P〈0.05）;大鼠ASMC PCNA表达与大鼠ASMC中VEGF及Flk-1蛋白质表达水平也呈正相关（r分别为0.80,0.77;P〈0.05）。结果 哮喘模型大鼠ASMC中VEGF及其受体Flk-1表达上调,并与气道平滑肌细胞增殖有密切关系。该结果提示VEGF及其受体2可能参与了哮喘气道重建中气道平滑肌细胞增殖的过程。

Objective To investigate the correlation of airway smooth muscle cell（ASMC） proliferation with expression of vascular endothelial growth factor（VEGF） and its receptor 2（Flk-1） in asthmatic rats.Methods Eighteen SD rats were randomly divided into three groups： the control group,the asthma model group and the dexamethasone group,and ASMCs in each group were cultured.The proliferation of ASMCs was examined by proliferating cell nuclear antigen（PCNA） with immunohistochemistry.Western blot and RT-PCR were used to measure the expression of protein and mRNA of VEGF and its receptor 2 in ASMCs.Results（1） The expression of PCNA of ASMCs in the asthma model group was higher than that in control and dexamethasone groups（P0.05）.（2） The expression of VEGF205,188,164mRNA and Flk-1mRNA in ASMCs of the asthma model group was higher than that in control and dexamethasone groups（P0.05 or P0.01）.（3） The expression of VEGF and Flk-1 proteins in ASMCs of the asthma model group was higher than that in control and dexamethasone groups（P0.05）.（4）The expression of VEGF205,188,164 and Flk-1 mRNA was positively correlated with that of PCNA（r=0.79,0.86,0.83,0.68;P0.05,respectively）.The expression of VEGF and Flk-1 proteins was also positively correlated with that of PCNA（r=0.80,0.77;P0.05,respectively）.Conclusion The expression of VEGF and Flk-1 was increased in ASMCs of asthmatic rats and positively correlated with the proliferation of ASMCs.VEGF and Flk-1 may take part in the process of ASMc proliferation in airway remodeling of asthma.