【摘要】 背景:研究表明在多种心脏疾病后的心室肌中HCN2和HCN4表达异常,且与室性心律失常密切相关。骨髓间充质干细胞移植可修复受损心肌,但对梗死后心室离子通道重构的影响仍不清楚。目的:检测大鼠骨髓间充质干细胞移植入梗死心肌后左心室HCN2和HCN4的表达变化。方法:取3周龄SD大鼠5只,Percoll法分离培养骨髓间充质干细胞。成年健康雄性SD大鼠30只,随机分为4组:DMEM组、细胞移植组大鼠建立急性心肌梗死模型,假手术组只穿线不结扎,正常对照组不进行任何干预。造模后4周,DMEM组在梗死边缘区和中心区分5点注入DMEM培养液,细胞移植组同法注入第3代骨髓间充质干细胞悬液200μL,细胞数5×106个。采用RT-PCR及Western-blot法检测左心室HCN2,HCN4在mRNA及蛋白水平的表达。结果与结论:正常心肌区:各组HCN2,HCN4 mRNA及蛋白的表达基本相似(P>0.05)。梗死边缘区:DMEM组HCN2,HCN4 mRNA及蛋白的表达明显多于正常对照组、假手术组(P<0.05);细胞移植组HCN2,HCN4 mRNA及蛋白的表达明显少于DMEM组(P<0.05)。梗死中心区:DMEM组HCN2,HCN4 mRNA及蛋白的表达明显少于正常对照组、假手术组(P<0.05);细胞移植组HCN2,HCN4 mRNA及蛋白的表达与DMEM组基本相似(P>0.05)。提示急性心肌梗死后梗死边缘区HCN2,HCN4基因在mRNA和蛋白水平的表达升高,骨髓间充质干细胞移植可能通过下调梗死边缘区HCN2,HCN4的表达来降低心律失常。更多还原

【Abstract】 BACKGROUND: Studies have demonstrated that hyperpolarization-activated andcyclic nucleotide-gated cation channels (HCN) 2 and HCN4 are abnormal expressed in ventricular muscle following heart disease, which is closely correlate to ventricular arrhythmia. Bone marrow stem cells (BMSCs) transplantation can improve damaged cardiac muscle; however, its effect on remodeling of ion channel is unclearly. OBJECTIVE: To detect the changes of HCN2 and HCN4 expression in left ventricle following BMSCs transplantation. METHODS: Five Sprague-Dawley (SD) rats, aged 3 weeks, were prepared for BMSCs by Percoll method. Additional 30 health, male, SD rats, were randomly divided into DMEM, cell transplantation, sham operation and control groups. At 4 weeks after model preparation, DMEM culture medium was injected into the infarcted area and surroundings with 5 points in the DMEM group. The 3rd generation of cultured BMSCs (200 μL, with 5×106 cells) were injected into rats in the cell transplantation group with the same methods. The mRNA and protein expression of HCN2 and HCN4 gene was detected by RT-PCR and Western blot respectively. RESULTS AND CONCLUSION: In non-infarcted region, the mRNA and protein expression of HCN2 and HCN4 among each groups had no significant difference (P > 0.05). Compared with the control and sham operation groups, mRNA and protein expression of HCN2 and HCN4 in surrounding of the infracted region was elevated in the DMEM group (P < 0.05), which was greater than that of the cell transplantation group (P < 0.05). The mRNA and protein expression of HCN2 and HCN4 was smaller in the center area of infracted region in the DMEM group than that of the control and sham operation groups (P < 0.05), which was similar to the cell transplantation group (P > 0.05). Acute myocardial infarction can increase mRNA and protein expression of HCN2 and HCN4 in infracted region surrounding. BMSCs transplantation may lower the fatality rate of ventricular arrhythmia by reducing HCN2 and HCN4 expression.更多还原