微创建立主动脉弓缩窄动物模型及超声评价  

Establishment of mouse model of transverse aortic constriction in a minimally invasive way and echocardiographic assessment

作　　者：徐洪[1] 臧旺福[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院心脏外科,200025

出　　处：《中华胸心血管外科杂志》2012年第9期544-548,共5页Chinese Journal of Thoracic and Cardiovascular Surgery

基　　金：2009年教育部博士点专项科研基金（20090073110086）

摘　　要：目的尝试一种新的用以观察左心室压力超负荷诱导左心室肥厚的主动脉弓缩窄动物模型。方法55只小鼠随机数字法分为重度缩窄组（sTAC，27只），中度缩窄组（mTAC，7只）以及假手术组（sham，21只）。采用微创改进的方法，在无名动脉和左颈总动脉之间结扎主动脉弓，构建不同程度的主动脉缩窄，造成中度或重度的左心室流出道机械梗阻。使用经胸二维以及M型超声监测术后4周压力超负荷诱导左心室肥厚的可靠性并评价其效果。结果成功建立34只小鼠模型，存活率88．2％（30／34只），手术小鼠术后顺利存活4周以上。主动脉弓缩窄后4周，经胸超声证实小鼠心脏呈现离心性肥厚表现，心脏收缩功能降低，主动脉弓中度缩窄小鼠的左心室短轴缩短分数（LVFS）从0．403±0．007降至0．340±0．015（P〈0．05），左心室较好地保留了收缩和舒张功能，心室肥厚呈代偿性；重度缩窄小鼠LVFS从0．438±0．011降至0．216±0．012（P〈0．01），心脏收缩功能明显减退，室壁活动僵硬甚至局部无活动，呈病理性失代偿性肥厚。结论微创方法在无名动脉和左颈总动脉之间结扎主动脉弓，构建不同程度的主动脉缩窄模型可重复性好，效果确切，术后小鼠存活率高，是一种值得推荐的左心室压力超负荷模型。Objective To explore the feasibility of establishing a modified mouse model of pressure overload induced left ventricular hypertrophy by transverse aortic constriction （TAC）. Methods 55 C57BL/6 female mice were randomly divided into three groups ： severe TAC group （ n = 27 ）, moderate TAC group （ n = 7 ） and sham surgery group （ n = 21 ）, respectively. By ligating the aorta arch between innominate artery and the left common carotid artery with modified techniques in a minimally invasive way, moderate or severe aortic constriction were established successfully and reliably to mimic left ventricular （LV） outflow obstruction; to correctly evaluate the cardiac structural and functional responses to aortic arch banding, 2-dimention （2D） and M mode transthoracic echocardiography （TTE） were deployed to monitor the LV contractile function and assess the LV hypertrophic changes induced by pressure overload at 4 weeks after the surgery. Results The mouse model of aortic constriction was established successfully with a post-operative survival rate more than 88%. And all these operated mice were able to survive at least 4 weeks long. Eccentric left ventricular hypertrophic changes were detected with echocardiographic measure- ment 4 weeks after the banding operation in both mTAC and sTAC group, as dilated left ventricular lumen with enlarged LV end-diastolic dimension （LVEDD） and LV end systolic- dimension （LVESD） were confirmed. Mice with moderate banded a- orta exhibited a compensated LV hypertrophy with preserved contractile functions and satisfactory ventricular wall movements to some extent, although left ventricular fractional shorting （LVFS） reduced gradually from 0. 403 ± 0. 007 to 0. 340 ± 0. 015 （ P 〈 0. 05 ） ; while in severe banded （sTAC） mice, LVFS reduced more significantly as a sharp decrease from 0. 438 ± 0. 011 to 0. 216 ± 0. 012 （ P 〈 0. 01 ） were detected, combined with poor contractile function and stiff ventricular wall movements, exhib- iting

关 键 词：主动脉缩窄 模型 动物 心脏扩大 小鼠 

分 类 号：R654.3[医药卫生—外科学] R-332[医药卫生—临床医学]