骨髓间充质干细胞体外定向诱导心肌样细胞的实验研究

目的研究兔骨髓间充质干细胞（mensenchymal stem cell，MSC）经5-氮杂胞苷（5-azacytidine，5-aza）诱导在体外定向分化为心肌样细胞形态学及分子生物学特征，为心肌样细胞鉴定提供依据。方法取兔髂骨骨髓，分离并培养骨髓间充质干细胞，用5-氮杂胞苷定向诱导向心肌样细胞分化。相差显微镜、透射电镜观察心肌样细胞形态学变化及超微结构特征，RT—PCR检测心房利钠肽、受磷蛋白、β-肌球蛋白重链表达。结果5-氮杂胞苷诱导后，部分细胞体积增大，呈“棒状”或“珠状”结构，有肌管样结构形成，透射电镜下有肌丝、心房颗粒及线粒体等心肌样细胞超微结构形成，RT—PCR检测显示有心房利钠肽、受磷蛋白、β-肌球蛋白重链表达。结论经5-氮杂胞苷诱导骨髓间充质干细胞体外可分化为心肌样细胞。

Experimental study on the differentiation of mesenchymal stem cells in bone marrow to cardiomyocytes in vitro

Objective To study myogetic differentiation of mesenchymy stem cells from rabbit bone marrow in vitro after induced by 5-azacytidine and to give a proof for identifying cardiomyocyte cell.Methods Isolated MSCs from rabbit bone marrow were cultured in cell cuture medium and in medium with 5-azacytidine,MSCs were identified by means of transmission electronmicroscopy technique and convert phase microscope technique.The expression of atrial natriuretic polypeptide,phospholamban and myosin heavy chain mRNA were also examined by RT-PCR.Results Some of cells became greater in size and had a stick or ball like,myotubes shape.Transmission electron microscopy showed that differentiated cells with oval nuclei positioned in the central part of the cell had well organized myofilaments,atrial granules and mitochondrion.The results of RT-PCR showed that differentiated cells had the expression of atrial natriuretic polypeptide,phospholamban and myosin heavy chain mRNA.Conclusion After induced by 5-azacytidine,mesenchymal stem cells can differented into cardiomyocyte cell in vitro.