转化生长因子β1对不同阶段支气管哮喘模型大鼠气道平滑肌细胞外信号调节激酶通道的影响

目的 本文旨在探讨转化生长因子β1(transforming growth factorβ1,TGF-β1)对不同阶段(急性和慢性)支气管哮喘(简称哮喘)大鼠气道平滑肌细胞(airway smooth muscle cells,ASMC)上细胞外信号调节激酶(extracellular signal-regulated kinase,ERK)1/2 mRNA、磷酸化ERK1/2(p-ERK1/2)表达水平的影响.方法 建立2周、6周哮喘大鼠模型,用TGF-β1和ERK的特异性抑制剂PD98059干预哮喘大鼠ASMC的培养.用RT-PCR检测不同阶段哮喘大鼠模型ASMC上ERK1/2 mRNA表达,免疫细胞化学染色法检测p-ERK1/2蛋白的表达及定位.结果 与正常对照组ASMC比较,2周、6周哮喘组ERK mRNA、ERK1/2蛋白、p-ERK1/2蛋白的表达量以及ERK活化率显著增高.经PD98059干预之后,2周、6周哮喘组ASMC的ERKmRNA、p-ERK1/2蛋白的表达量以及ERK活化率均显著降低.经TGF-β1干预后,2周、6周哮喘组ASMC的ERK mRNA、p-ERK1/2蛋白的表达量较各自哮喘组显著增高,而这一作用可以被PD98059部分抑制.但以上结果 2周和6周哮喘模型组之间差异无统计学意义.结论 TGF-β1可上调不同阶段哮喘大鼠ASMC上ERK1/2 mRNA及p-ERK1/2表达.在哮喘的不同阶段,TGF-β1可能持续通过促进ERK信号转导通道的活性对ASMC的增殖进行调控.

Effect of transforming growth factor β1 on the activity of extracellular signal-regulated kinase1/2 of airway smooth muscle cells in different periods of asthmatic rats

Objective To investigate the effect of transforming growth factor β1 (TGF-β1) on airway smooth muscle cells (ASMC) expression of extracellular signal-regulated kinase (ERK)1/2 mRNA and phosphorylated forms of ERK1/2 (p-ERK1/2) in different periods asthmatic rats. Methods The establishment of 2W, 6W rat model of asthma through ovalbumin (OVA) sensitization and excitation.TGF-β1 and ERK inhibitor PD98059 were used in the cell culture. The expressions of ERK1/2 mRNA were detected by RT-PCR, the location and protein expressions of p-ERK1/2 were examined by immunocytochemical staining. Results The results showed that in 2W, 6W asthmatic groups, compared with that in the control group,the expressions of ERK mRNA, p-ERK1/2 protein and the activation ratio of ERK in ASMC in asthmatic groups were significantly increased compared with those in the control group. After treatment with PD98059, the expressions of ERK mRNA, p-ERK1/2 protein and the activation ratio of ERK in ASMC in asthmatic groups were significantly decreased compared with those in the control group. After treatment with group TGF-β1 ,the expressions of ERK mRNA,p-ERK1/2 protein and the activation ratio of ERK in ASMC in 2W and 6W asthmatic group were significantly decreased compared with those in their asthmatic group. And this role can be partly inhibited by PD98059. There is no difference between the 2W and 6W asthmatic model group with these results. Conclusions TGF-β1 upregulated expression of ERK1/2 mRNA and p-ERK1/2 in different periods asthmatic rats, at different stages of asthma,TGF-β1 is likely to continue through the promotion of ERK signal transduction pathway of the activity on the proliferation of ASMC regulate.