目的：通过分析microRNA-208在急性心肌梗死(acute myocardial infarction，AMI)患者外周血中含 量的变化，探讨microRNA-208在AMI疾病进展中的作用。方法：连续性收集2013年1月~2013年12 月滁州市第一人民医院心血管内科和急诊科收治的急性心肌梗死(AMI)患者42例，不稳定心绞痛 (unstable angina，UA)患者22例，健康体检志愿者20名，荧光定量 PCR测定外周血microRNA-208的 含量，电化学发光法检测血浆cTnI和CK-MB的水平。AMI组患者根据不同冠脉病变支数和接受急 诊经皮冠状动脉介入(percutaneous coronary intervention，PCI)治疗进行分组，对比各组患者外周 血microRNA-208水平的差异。结果：AMI患者外周血microRNA-208的水平显著高于UA组和健康对 照组，差异具有统计学意义(P<0.01)，AMI患者外周血microRNA-208的水平与血清CTnI含量呈正 相关(r=0.700，P=0.000)。24例行冠状动脉造影术的AMI组患者中，microRNA-208的表达在两支及 三支病变中高于单支病变(P<0.01)，17例成功接受急诊PCI治疗的AMI患者，其症状发作后的24h 血浆microRNA-208水平较入院即刻时明显降低(P<0.01)。结论：心肌细胞特异性的microRNA-208 在心肌梗死后外周血含量明显升高，随着血管狭窄严重程度的升高其浓度也显著变化，可以作为 辅助监测急性心肌梗死的敏感的生物学指标。
Changes of microRNA-208 level in plasma of acute myocardial infarction patient and its clinical significance
Objective: To study the change of cardio-specific microRNA-208 levels in acute myocardial infarction patients and to explore the effect of microRNA-208 levels on the diagnosis of AMI. Methods: The consecutive subjects in roll in this study, including 42 patients with AMI, 22 patients with UA and 40 healthy subjects in our hospital from January 2013 to December 2013, microRNA-208 concentrations were measured with real-time reversetranscription PCR, all the clinical data of patients was collected. AMI patients were further divided into subgroups according to coronary arteries involved and primary PCI or not, Plasma microRNA-208 concentrations were analyzed. Serum Cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) concentrations were measured. Results: microRNA-208 expression was significantly higher in the AMI patients than that in the UA patients group and healthy controls immediately after admission (P<0.01). The Plasma microRNA-208 in the patients with AMI had a positive correlation with serum cTnI (P<0.01). MicroRNA-208 levels in AMI patients with twoand three-vessel coronary artery disease (CAD) were significantly higher than those in patients with single vessel CAD (P<0.05). microRNA-208 level at admission was significantly higher than that 24h after PCI in AMI patients (P<0.01). Conclusion: The circulation miRNA-208 was found to be linearly to myocardial damage and may prove to be a new biomarker of AMI.