中文摘要：

目的研究MHP36神经干细胞在体外经Ⅳ型胶原诱导向平滑肌细胞的分化潜能。方法体外培养MHP36神经干细胞，采用Ⅳ型胶原在37℃培养箱促分化，在分化第1、2、4天分别收获细胞并通过PCR和Western免疫印迹分别检测平滑肌细胞特异性标志物（SMαA，SMMHC，SM22，Myocardin）基因和蛋白表达。最后对分化第4天的细胞进行细胞免疫荧光染色来鉴定SMαA、SMMHC的表达。结果MHP36神经干细胞在37℃培养条件下从第2天开始逐渐变长、呈梭形，并在培养基中形成螺旋状结构。PCR及免疫印迹证实SMαA，SMMHC，SM22，Myocardin的基因和蛋白表达从分化第1天到第4天显著增加（P〈0．05）。此外，分化第4天的细胞表达成熟的SMαA，SMMHC胞浆蛋白。结论MHP36神经干细胞在体外经Ⅳ型胶原诱导可向平滑肌细胞分化，并表达平滑肌细胞的特异性标志物。

英文摘要：

Objective To investigate the differentiation of MHP36 neural stem cells towards smooth muscle cells in vitro. Methods MHP36 neural stem cells were induced to differentiate into smooth muscle cells （SMCs） on type Ⅳ col- lagen coated flasks at 37℃. Cells were harvested for mRNA and protein extraction on the 1st, 2nd and 4th day in differ- entiation medium. The mRNA and protein expresion of SMCs-specific markers （SMαA, SMMHC, SM22, Myocardin） were detected by PCR and Western blot. Finally, the differentiating cells on the 4th day were prepared for immunofluo- rescenee staining using antibodies of SMαA and SMMHC. Results MHP36 neural stem cell lost their neural shape from the 2nd day of differentiation and became long, spindle-shaped and started to form a spiral structure on the flasks. PCR and Western blot confirmed that gene and protein expression of SMαA, SMMHC, SM22 and Myocardin were gradually increased from the 1st day of differentiationfrom, with statistical significance（P〈0.05）. In addition, the differentiating cells on the 4th day expressed mature smooth muscle actin and myosin fibers, as shown by significant staining of SMαA and SMMHC. Conclusions MHP36 neural stem cells are successfully induced to differentiate into SMCs on type Ⅳ col- lagen coated flasks at 37℃ , which is proved by the gene and protein expression of specific markers of SMCs.