【摘要】 目的建立心脏特异表达Calponin 1转基因小鼠,研究Calponin 1对心脏发育及心肌病的调节作用。方法利用心脏特异启动子α-MHC构建转基因表达载体,显微注射法建立Calponin 1转基因小鼠,PCR法鉴定转基因小鼠的基因型,Western Blot检测Calponin 1在心脏组织中的表达,心脏超声检测转基因小鼠的心脏结构和功能,HE染色和Masson染色检测转基因小鼠心脏的病理改变。结果 Calponin 1在野生型小鼠心脏中有表达,在扩张型心肌病小鼠的心脏组织表达降低。通过显微注射法,建立了2个心脏组织Calponin 1基因高表达的转基因小鼠系。与野生型小鼠相比,Calponin 1转基因小鼠收缩期左室内径(LVID,systolic)增加28%(P<0.01,n=12),舒张期左室内径(LVID,diastolic)增加16.2%(P<0.01,n=12),收缩期左室后壁厚度(LVPW,systolic)减小15.7%(P<0.01,n=12),舒张期左室后壁厚度(LVPW,diastolic)减小21%(P<0.01,n=12),射血分数(ejection fraction,EF)降低11.5%(P<0.01,n=12),短轴内径缩短率(fraction shortening,FS)降低14.6%(P<0.05,n=12)。转基因小鼠心脏组织病理H&E染色和Masson染色显示,转基因小鼠心室扩张,心肌细胞不均匀肥大,细胞间隙变大,心肌间质纤维增多。结论 Calponin 1在心脏特异过表达引起转基因小鼠心脏左室内径增加,收缩期容积和舒张期容积显著增大,心室壁变薄,射血分数及短轴缩短率降低等扩张性心肌病表型,推测Calponin 1是参与心肌病病理发生的基因之一。更多还原

【Abstract】 Objective To establish the heart-specific expression Calponin 1 transgenic mice and investigate its effects on the development of heart and cardiomyopathy.Method The transgenic vector was constructed by inserting the human Calponin 1 gene into the down-stream of α-MHC promoter.The transgenic mice were generated by the method of microinjection.The genotype of transgenic lines was identified by PCR,and the expression levels of the Calponin 1 genewere detected by Western Blot.The pathologic changes of the heart structure and function were analyzed by echocardiography,hematoxylin and eosin(HE) stain and Masson stain.Result The expression of Calponin 1 was detected in the heart of different age wide-type mice by Western Blot,but was down-regulated in the mice with DCM.Compared with the wild type mice,transgenic mice showed significant heart remodeling,left ventricular systolic diameter increased by 28%(P < 0.01,n = 12),left ventricular diastolic diameter elevated by 16.2%(P < 0.01,n = 12),left ventricular posterior wall during systolic decreased by 15.7%(P < 0.01,n = 12),and left ventricular posterior wall during diastole reduced by 21%(P < 0.01,n = 12).Transgenic mice,versed wild type,showed weakened heart function,ejection fraction diminished by 11.5%(P < 0.01,n = 12) and fraction shortening reduced by 14.6%(P < 0.05,n = 12).The heart of the transgenic mice exhibited an enlarged ventricular chamber when compared with that of the wild type with HE stain and Masson stain.Conclusion Over-expression of Calponin 1 in the heart of the transgenic mice caused a phenotype similar with dilated cardiomyopathy.It suggested that Calponin 1 might be one of the modifier genes which involved in the pathogenesis of cardiomyopathy.更多还原