高频超声在主动脉弓缩窄术诱导小鼠心力衰竭模型中的早期应用评估

High frequency Doppler echocardiography in early evaluation of transverse aortic constriction in- duced heart failure mice

目的利用高频多普勒超声早期检测主动脉弓缩窄程度，探讨小鼠主动脉弓缩窄诱导心力衰竭模型建立的可靠性和稳定性。方法C57／BL6小鼠经手术缩窄主动脉弓建立心力衰竭模型，通过术后早期检测升主动脉和主动脉弓缩窄处血流速度评估主动脉弓缩窄程度，结合超声检测小鼠左室射血分数和缩短分数，最终与分子生物学指标和病理学结果验证心力衰竭模型建立的可靠性和稳定性。结果主动脉弓缩窄小鼠术后8周的存活率为83．3％；主动脉弓缩窄程度平均为（75．8±1．3）％；与假手术组比较，主动脉弓缩窄小鼠在术后2周开始出现心功能下降，一直持续至术后8周，术后8周心脏重量指数显著增加（P〈0．01），病理学检查发现心腔扩大，纤维化明显。反映心功能的分子生物学指标心钠肽（ANP）、脑钠肽（BNP）、β-肌球蛋白重链（β-MHC）显著升高（P〈0．01）。结论高频多普勒超声早期检测小鼠主动脉弓缩窄处狭窄程度评估心力衰竭模型建立可靠性的方法，有助于早期判断心力衰竭建模成功与否和发展时程，有助于筛选合适样本进行相应分子生物学检测和基因学检测。

Objective To evaluate the stability and reliability of heart failure model by using high frequency Doppler echoeardiography to early assess the stenosis of transverse aortic constriction （TAC） of mice. Methods Heart failure model on C57/BL6 mice was set up by TAC. By using high frequency Doppler echocardiography to detect the blood flow of ascending aorta and the site of constriction 3 - 5 days after TAC, together with ejection fraction and fraction shortening, molecular marker and histology result, the relationship between stenosis of constriction and heart function was analyzed. Results The survival rate of TAC mice after 8 weeks was 83.3%. The average stenosis of constriction was （75.8 ± 1.3）%. Compared to Sham group, TAC mice got declined heart function after 2 weeks until 8 weeks. Histology re- suits showed dilated heart and increased fibrosis. Atrial natriuretic peptide （ANP） and brain natriuretic peptide （ BNP）, and β - myosin heavy chain （ β - MHC） were markedly increased after 8 weeks. Conclusion High frequency Doppler echocardiography could early assess the stenosis of constriction in TAC mice and could contribute to evaluate the stability and reliability of heart failure model and to screen suitable samples for further research.