房室传导阻滞模式小鼠的建立

发布时间：2018-06-24 13:33

本文选题：KCNQ1 + 房室传导阻滞　；参考：《同济大学》2006年硕士论文

【摘要】： 背景房室传导阻滞可见于部分心房颤动患者，然而其分子机制并不清楚。三年前陈等报道KCNQ1基因S140G突变可以引起家族性心房颤动，同时通过动态心电图检查发现这个家系中大部分心房颤动患者合并房室传导阻滞，KCNQ1 S140G突变与房室传导阻滞共分离。因此我们推测房室传导阻滞与心房颤动可能有相同的分子变异基础。目的建立转KCNQ1 S140G突变体小鼠模型，进一步明确KCNQ1 S140G突变体致心房颤动和或致房室传导阻滞的病理生理作用。方法提取正常人的心肌组织RNA，，逆转录得到cDNA，亚克隆入心肌特异性表达载体，定点诱变得到KCNQ1 S140G，经测序证实无误后线性化借助显微注射装置将其注射入受精卵，移入代孕小鼠输卵管，进行繁殖而建立人S140G突变型KCNQ1心肌特异性表达转基因小鼠模型，对该模型进行遗传学检测、表达分析和表型检测。结果我们成功建立了人S140G突变型KCNQ1转基因小鼠模型，四品系转基因模式小鼠的心脏中均高度表达KCNQ1 S140G突变体，对照组未见突变表达。小鼠体表心电图检测发现65％阳性小鼠有一度、二度、高度和三度房室传导阻滞事件，但未见心房颤动表型，而未含有该突变的对照小鼠既未发现房室传导阻滞也未见心房颤动事件。结论1．S140G突变型KCNQ1心肌特异性过表达可以引起小鼠房室传导阻滞，但是不能复制出心房颤动表型；2．KCNQ1的分子缺陷不但与人类心房颤动有关，而且还可引起人类和小鼠房室传导阻滞；3．S140G突变型KCNQ1转基因小鼠模型可能是探索房室传导阻滞病理生理机制和药物干预的良好工具。
[Abstract]:Background atrioventricular block is seen in some patients with atrial fibrillation, but its molecular mechanism is unclear. Chen et al reported three years ago that S140G mutation of KCNQ1 gene could cause familial atrial fibrillation. At the same time, it was found that KCNQ1 S140G mutation was separated from atrioventricular block in most patients with atrial fibrillation in this pedigree by dynamic electrocardiogram. Therefore, we speculate that atrioventricular block and atrial fibrillation may have the same molecular basis of variation. Objective to establish a mouse model of KCNQ1 S140G mutant and to further clarify the pathophysiological effects of KCNQ1 S140G mutant on atrial fibrillation and atrioventricular block. Methods normal human myocardial RNAs were extracted, cDNA was obtained by reverse transcription and subcloned into myocardial specific expression vector. KCNQ1 S140G was obtained by site-directed mutagenesis. After sequencing, it was linearized and injected into fertilized eggs by microinjection device. The transgenic mouse model of specific expression of human S140G mutant KCNQ1 was established by transferring into the fallopian tube of surrogate mice. The genetic analysis, expression analysis and phenotypic detection of the model were carried out. Results the human S140G mutant KCNQ1 transgenic mouse model was successfully established. KCNQ1 S140G mutant was highly expressed in the heart of the four strain transgenic mice, but no mutation was found in the control group. Body surface electrocardiogram showed that 65% of the positive mice had once, second, high and third degree atrioventricular block events, but no phenotype of atrial fibrillation. Neither atrioventricular block nor atrial fibrillation was found in the control mice without the mutation. Conclusion 1.Myocardial specific overexpression of S140G mutant KCNQ1 can induce atrioventricular block in mice, but it can not replicate the phenotype of atrial fibrillation. 2. The molecular defect of KCNQ1 is not only related to human atrial fibrillation. Moreover, the transgenic mouse model of KCNQ1 mutant 3.S140G may be a good tool to explore the pathophysiological mechanism of atrioventricular block and drug intervention.
【学位授予单位】：同济大学
【学位级别】：硕士
【学位授予年份】：2006
【分类号】：R-332;R541.7

【参考文献】