中文摘要：

目的：建立心肌特异性Creg基因敲除小鼠并初步分析其表型。方法：利用订购的Creg两端插入lox P位点（Creg^flox/flox）的小鼠与肌型肌酸激酶特异性启动子驱动的Cre重组酶转基因（Ckmm-cre）小鼠交配,获得Creg^flox/＋/Ckmm-cre小鼠。再利用Creg^flox/＋/Ckmm-cre小鼠互相交配,获得基因型为Creg^flox/flox/Ckmm-cre的心肌特异性Creg基因条件敲除（Creg conditional knockout,Creg c KO）小鼠。用PCR法进行基因型鉴定。用定量PCR及Western Blot检测心肌组织中Creg表达水平。HE染色观察敲除小鼠与同窝野生型对照小鼠心脏大小及形态。检测两组小鼠心电图。用小动物超声评价两组小鼠左心室收缩功能。结果：①经基因型鉴定,成功获得Creg c KO小鼠。②与野生型对照相比,Creg c KO小鼠心脏中CREG在转录及翻译水平表达降低90%以上。③与野生型对照相比,Cre c KO小鼠的心脏大小、形态、心电图及左心室射血分数均无显著差别。结论：成功建立心肌特异性CREG基因条件敲除小鼠,为进一步研究Creg在心脏疾病中的作用和机制提供了有力的工具。

英文摘要：

Objective： To establish cardiac-specific Creg gene knockout mice and analyze their phenotype. Methods： Ordered mice with Creg gene flanked by loxP （Creg^flox/flox） were crossed with transgenic mice with Cre recombinase gene driven by muscle creatine kinase （Ckmm-cre） promoter to obtain Creg^flox/＋/Ckrnm-cre mice. Then mutual mating was carried out in Creg^flox/＋/Ckmm-cre mice to establish cardiac specific Creg conditional knockout （Creg cKO） mice with a genotype of Creg^flox/fox/Ckmm-cre. Genotyping was realized by PCR. Expression of Creg gene in heart tissue was determined by Real-time PCR and Western Blot. Size and morphology of hearts from knockout mice and their wild type littermates were assessed by HE staining. Electrocardiography （ECG） was recorded and left ventricular contractility was measured by small animal echocardiography. Results： （1） Creg cKO mice were successfully established and confirmed by genotyping. （2） Compared with wild type control, Creg cKO mice showed no significant change in size and morphology of heart, ECG and ejection fraction of left ventricle. Conclusion： We successfully established cardiac-specific Creg cKO mice, which will provide powerful tools for further investigations on the role and mechanism of CREG in heart diseases.