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目的:探索骨形态发生蛋白7（bone morphogenetic protein 7, BMP7）在体外诱导大鼠骨髓间质干细胞分化为神经元的作用。方法:SPF级SD大鼠10只，雄性，4周龄，体重约110 g，以全骨髓贴壁法分离、培养大鼠骨髓间质干细胞（bone marrow mesenchymal stem cells, BMSCs）；成脂诱导、成骨分化检测BMSCs多向分化能力。将BMSCs随机分为对照组、25 ng/ml、50 ng/ml、75 ng/ml及100 ng/ml BMP7组，MTT法检测BMP7对大鼠BMSCs增殖的影响；倒置相差显微镜下观察大鼠BMSCs诱导后形态学变化；qRT-PCR检测诱导得到的细胞NF200、SYN1、MAP2、GFAP mRNA相对表达量；免疫荧光检测NSE蛋白表达情况。结果:体外培养的第3代大鼠BMSCs呈长梭形，细胞聚集生长呈漩涡状。大鼠BMSCs成脂诱导后胞浆内出现脂滴，油红“O”染色呈阳性；大鼠BMSCs经成骨诱导后出现不透光团状矿物质结节，茜素红染色呈阳性。诱导1后第1天，各组细胞吸光度值比较差异无统计学意义；诱导后2~6 d，各组细胞吸光度值比较差异有统计学意义（均n P< 0.05），诱导后第6天时，对照组、25 ng/ml、50 ng/ml、75 ng/ml、100 ng/ml BMP7组吸光度值分别为0.370±0.003、0.399±0.003、0.404±0.003、0.410±0.003、0.397±0.001，其中75 ng/ml BMP7组细胞吸光度值明显高于其余各组（均n P< 0.05）。75 ng/ml BMP7组细胞形态学变化最为显著，细胞形态上类似神经元。75 ng/ml BMP7组NF200、SYN1、MAP2、GFAP mRNA相对表达量分别为5.47±0.59、1.48±0.38、2.86±1.65、4.41±0.13，均显著高于对照组（均n P< 0.05）。75 ng/ml BMP7组NSE免疫荧光染色阳性率高于对照组（32.94%±1.62%比0）。n 结论:BMP7具有体外诱导大鼠BMSCs分化为神经元的能力。“,”Objective:To explore the role of BMP7 in inducing the differentiation of BMSCs into neurons in vitro.Methods:BMSCs were isolated and cultured by whole bone marrow adherence method. Adipogenic induction and osteogenic differentiation were used to test the multi-directional differentiation ability of BMSCs. BMSCs were randomly divided into control group and BMP7 groups (25 ng/ml, 50 ng/ml, 75 ng/ml and 100 ng/ml). The effect of BMP7 on the proliferation of rat BMSCs was measured by MTT assay. BMP7 induced morphological changes in rat BMSCS under an inverted phase contrast microscope. The relative expression levels of NF200, SYN1, MAP2 and GFAP mRNA in induced cells were measured by qRT-PCR. Immunofluorescence was used to measure the expression of NSE protein.Results:Rat BMSCs showed lipid droplets in the cytoplasm after adipogenic induction, and oil red O staining was positive; rat BMSCs showed opaque mineral nodules after osteogenic induction, and alizarin red stained was positive. At 2 d, 3 d, 4 d, 5 d, and 6 d after induction, the cell absorbance values of each group were statistically different (n P < 0.05). On the 6th day of induction, the absorbance values of the control group, 25 ng/ml BMP7 group, 50 ng/ml BMP7 group, 75 ng/ml BMP7 group and 100 ng/ml BMP7 group were 0.370±0.003, 0.399±0.003, 0.404±0.003, 0.410±0.003, 0.397±0.001, respectively. Cells absorbance value of 75 ng/ml BMP7 group was significantly higher than the other groups ( n P< 0.05). The 75 ng/ml BMP7 group had the most significant changes in cell morphology, similar to neurons in cell morphology. The relative expression of NF200, SYN1, MAP2, and GFAP mRNA of 75 ng/ml BMP7 group (5.47±0.59, 1.48±0.38, 2.86±1.65, 4.41±0.13) was significantly higher than that of the control group (n P< 0.05). The positive rate of NSE immunofluorescence staining in the 75 ng/ml BMP7 group was higher than that in the control group (32.94%±1.62%n vs 0).n Conclusion:BMP7 has the ability to induce the differentiation of rat BMSCs into neurons in vitro.