摘要
【目的】体外诱导大鼠骨髓间充质干细胞(MSCs)分化为心肌细胞并探讨其内向整流钾电流(IK1)特征。【方法】采用密度梯度离心法和贴壁培养法分离、纯化大鼠骨髓MSCs,在第3代细胞以5-氮杂胞苷进行诱导,用免疫细胞化学染色和RT-PCR方法鉴定诱导细胞,并采用全细胞膜片钳技术检测IK1表达。【结果】诱导后细胞体积较诱导前增大,呈长梭形。14d后细胞之间出现连接,排列方向渐趋一致。免疫细胞化学染色显示Desmin、α-sarcomericactin和心肌特异性cTnI呈阳性反应,RT-PCR结果表明诱导细胞有心肌β肌球蛋白重链表达。诱导细胞IK1表达呈明显的不均一性,部分细胞IK1与正常心室肌细胞相似,但IK1电流密度总体上低于正常心室肌细胞。【结论】5-氮杂胞苷能在体外诱导MSCs向心肌细胞分化;诱导细胞IK1表达不均一性提示可能有致心律失常潜能。
[Objective] To study the differentiation of rat bone marrow mesenchymal stem cells (MSCs) into cardiomyocytes in vitro and the characteristics of inward rectifier potassium current (IK1) of induced cells. [Methods] MSCs were isolated and purified from the bone marrow of rats by density gradient centrifugation and adhering to the culture plastic. The third passage MSCs were treated by 5-azacytidine (5-aza). The expression of Desmin,α-actin and Troponin I were observed by immunocytochemistry staining. Whole cell patch clamp technique was used to record IK1. [Results]After being induced by 5-aza, some MSCs became bigger and longer. The connection of the cells was formed. The direction of the cells arraying was similar gradually. The cells were stained positively for Desmin, α-actin and Troponin I. RT-PCR showed that these cells expressed β myosin heavy chain. IK1 of some induced cells was similar to ventricular myocardial cells of normal rats. On average, IK1 was lower in induced cells than in ventricular myocardial cells. [Conclusion] 5-aza may induce MSCs to differentiate into cardiomyocytes in vitro. Induced cells demonstrate arrhythmic potential owing to heterogeneity of IK1.
出处
《中山大学学报（医学科学版）》
CAS
CSCD
北大核心
2005年第4期396-399,共4页
Journal of Sun Yat-Sen University:Medical Sciences
基金
广东省卫生厅科研基金资助项目(A2004200)
