中文摘要：

目的：研究β2肾上腺素能激动剂福莫特罗（Formoterol）对大鼠的体外骨髓间充质干细胞（MMSC）向成骨细胞分化的影响,进而探讨其作用机制。方法：取SD大鼠的骨髓间充质干细胞,用条件培养液诱导分化后分别加入不同浓度药物,在不同时间点采用RT-PCR法检测细胞分化中Runx2和Osterix的mRNA的表达,采用westernblot法检测细胞中MEK和ERK1/2的磷酸化。结果：在细胞分化早期,加入已知浓度10-7mol/L的Formoterol可抑制成骨样细胞细胞特异性转录因子Runx2mRNA表达;在细胞分化晚期,浓度10-7mol/L的Formoterol也可抑制成骨样细胞OsterixmRNA表达。在加入浓度10-7mol/的Formoterol作用30min后,MEK和ERK1/2的蛋白磷酸化表达均下降。结论：β2受体激动剂可抑制MMSC细胞体外向成骨样细胞的分化,并且可抑制MEK和ERK1/2磷酸化的表达。

英文摘要：

Objective：To observe the effects of Formoterol（β2-adrenergic receptor-specific agonist）on the differentiation of rat osteoblast-like cells.Methods：Osterix and RUNX2 are osteoblast-specific transcriptional factors that are essential for osteoblast differentiation and bone formation.RT-PCR was used to detect the Osterix and RUNX2 genes expressions during the treatment of different drug dose,the expression of P-MEK and P-ERK1/2 were measured by western blot.Results：①The mRNA expression of cells cultured with a concentration of 10-7mol/L of Formoterol are obviously low.②The protein phosphorylation of ERK and MEK in osteroblasts decreased at 30min treating the cells with Formoterol.Conclusions：In the present study,we examined the molecular mechanism of Osterix and RUNX2 gene expression,and found that Formoterol inhibited Osterix and RUNX2 expression in the mouse osteoblast-like cells,Formoterol-induced decrease of Osterix and RUNX2 expression may occurred in dose-dependent manner through the activation of extracellular signal-regulated kinase pathway.