中文摘要：

目的初步探讨血小板衍生生长因子（PDGF）对成神经细胞分化不同阶段骨髓间充质干细胞（BMSCs）趋化性迁移的影响。方法密度梯度离心和贴壁培养法分离培养BMSCs,并予以传代。用碱性成纤维细胞生长因子（bFGF）和丁羟基茴香醚（BHA）相结合的方法诱导BMSCs向成神经细胞分化,并用特异性标志物进行鉴定,利用Dunn chamber建立体外迁移模型,评估PDGF对不同分化阶段BMSCs定向迁移的影响。结果通过密度梯度离心和贴壁培养法获得了纯化的大鼠BMSCs。诱导组BMSCs变为神经元样细胞,而对照组的BMSCs形态无变化。Dunn chamber分析显示,分化不同阶段的BMSCs对PDGF的趋化程度不同：和对照组相比较,未诱导的BMSCs、预诱导24h和诱导5h的分化细胞的迁移速率得到明显提高（P〈0.05）;而未诱导的BMSCs、维持18h和维持48h的分化细胞的迁移效率明显升高（P〈0.05）。结论 BMSCs可以被诱导分化为神经样细胞;分化不同时期的细胞有不同的迁移能力。

英文摘要：

Objective To study the effect of platelet-derived growth factor（PDGF） on the tropism of different phases of bone mesenchymal stem cells（BMSCs） in neurogenic differentiation.Methods BMSCs were isolated and cultivated from the bone marrow of SD rats by Percoll gradient centrifugation.BHA and bFGF were used to induce BMSCs to differentiate into neural-like cells.Dunn chamber was chosen to study the effect of PDGF on BMSCs migration in vitro.Results BMSCs were successfully subcultured and purified by density gradient centrifugation and adherent culture method.BMSCs could be induced to differentiate into neuron-like cells,while the control remained the morphology of BMSCs.Dunn chamber analysis revealed that BMSCs at different states of differentiation showed different extend of tropism for PDGF：compared with the controls,the migration speed of undifferentiated BMSCs,BMSCs preinducing for 24 h and inducing for 5 h were significantly increased（P〈0. 05） ;while the migration efficiency of undifferentiated BMSCs,BMSCs maintaining for 18 h and 48 h were increased notablely（P〈0. 05）.Conclusion BMSCs can be induced to differentiate into neuron-like cells;the directed migration of BMSCs is closely related to the differetiation states of these cells.