斑点追踪超声心动图和心肌造影超声心动图监测大鼠糖尿病心肌病治疗疗效的实验研究

Diabetic cardiomyopathy(DCM)is one of the major lethiferous factors of diabetes mellitus. It is currently imperative to search for a accurate and simple method for detecting DCM and monitoring its therapeutic effectt.We found that at the early stage of DCM ,the myocardial strain ，strain rate and blood flow reserve were significantly reduced, and that was significant correlated with the pathological and functional results .It suggests that these indexes can be used as a sensitive indicator for the early diagnosis of DCM and have a potentially particular advantage on monitoring the therapeutic efficacy of DCM. In the present study,we will use speckle tracking echocardiography (STE) and myocardial contrast echocardiography(MCE) techology to observe the myocardial function and perfusion of DCM rats which will be treated by insulin with different starting time.After that , myocardium will be collected for transmission electron microscope and molecular biological examination.In the end,we will get an objective conclusion about the curative effect.The research aims at :1.To prove the feasibility of STE combined with MCE as a tool for evaluating curative effect of DCM rats,and search for indicators that has a high sensitivity and specificity.2.We should found such a proper time once being treated , it would effectively delay the deterioration of myocardial function.The study will connect macroscopical with microcosmic reasearch, enrich the theoretical foundation, and produce a effective method and the experimental bases for early dignosis of DCM and assessment of it's threapeutic effect.

糖尿病心肌病（DCM）是糖尿病死亡的主要原因之一，寻找准确、简便的DCM检测和疗效监测方法是当前迫切需要解决的问题。我们前期研究发现DCM早期大鼠心肌应变、应变率及血流储备指标均明显减低，且与病理及功能学结果显著相关，提示这些指标可作为DCM早期诊断的敏感指标，同时它们还可能在DCM疗效监测方面具有潜在而独特的优势。本研究拟针对不同时间点开始早期药物干预DCM大鼠，应用斑点追踪超声心动图（STE）和心肌造影超声心动图（MCE），连续、动态观察大鼠心肌功能和微循环灌注的变化，与电镜及分子生物学检查结合，对疗效作出客观评价。目的：1.论证STE和MCE结合作为DCM疗效评价工具的可行性，并选出灵敏度和特异度较高的定量评定指标。2.寻找最佳药物干预时间，以期有效阻止或延缓心肌功能恶化。本研究将架起宏观与微观的桥梁，充实前期理论基础，为DCM的早期诊断及疗效监测提供可靠的方法和实验依据。

糖尿病心肌病（DCM）是糖尿病死亡的主要原因之一。近年来对于DCM早期发病机制及早期干预治疗备受关注。早期DCM心肌功能的改变可能是基于心肌细胞内Ca2+负载变化和CaMKⅡδ表达降低。其在DCM的发生、发展过程中对于心肌血流灌注和功能的变化及不同时间点药物治疗后心肌血流灌注和功能的变化，以及早期药物干预后疗效评价颇为重要。本研究运用斑点追踪心动图（STE）和心肌造影超声心动图（MCE）技术结合心肌细胞电偶联及病理组织学检查在DCM大鼠不同时间点及不同干预治疗条件下发现心肌功能障碍和血流灌注异常，说明DCM大鼠的发生和早期发展阶段以心肌自身损伤为主，早期干预治疗对DCM大鼠心肌血流灌注和功能改善有显著疗效，VVI和MCE技术早期检测心功能和心肌血流灌注最为敏感。进而为DCM的早期诊断和干预治疗提供了实验依据和有效的检测方法。