超声心动图方法和协议心脏瓣膜疾病的综合表型特征小鼠
Summary
This protocol provides a detailed description of the echocardiographic approach for comprehensive phenotyping of heart and heart valve function in mice.
Abstract
The aim of this manuscript and accompanying video is to provide an overview of the methods and approaches used for imaging heart valve function in rodents, with detailed descriptions of the appropriate methods for anesthesia, the echocardiographic windows used, the imaging planes and probe orientations for image acquisition, the methods for data analysis, and the limitations of emerging technologies for the evaluation of cardiac and valvular function. Importantly, we also highlight several future areas of research in cardiac and heart valve imaging that may be leveraged to gain insights into the pathogenesis of valve disease in preclinical animal models. We propose that using a systematic approach to evaluating cardiac and heart valve function in mice can result in more robust and reproducible data, as well as facilitate the discovery of previously underappreciated phenotypes in genetically-altered and/or physiologically-stressed mice.
Introduction
衰老与心血管钙化1逐步增加有关。血液动力学显著主动脉瓣狭窄影响了人口的65 2岁以上的3％，而患者甚至中度主动脉瓣狭窄（3-4米/秒峰值速度）小于40％，5年无事件生存率3。目前，有减缓主动脉瓣钙化的进展没有有效的治疗，和手术主动脉瓣置换为先进主动脉瓣狭窄4唯一可用的治疗方法。
旨在获得有助于启动和主动脉瓣钙化进展的机制有更深的了解研究是在走向药理和非手术方法来管理主动脉瓣狭窄5,6的关键的第一步。遗传学LY-改造的小鼠都起到了我们的开发有助于各种疾病，现在即将旨在了解主动脉瓣狭窄6，7，8的生物学机理研究的最前沿机制的理解了重大作用。不像其他心血管疾病如动脉粥样硬化和心脏衰竭，其中用于评估血管和心室功能标准协议是行之有效的，存在与小鼠心脏瓣膜功能的体内表型相关的独特的挑战的大部分。虽然最近的评论已提供了有关的优点和缺点，以众多的成像和用于评估在啮齿类动物中9，10，11阀功能侵入性的方式充分的讨论，到今天为止，我们不知道它提供了一个COMPRE出版物的hensive，一步一步在小鼠表型心脏瓣膜功能的协议。
本手稿的目的是描述该方法和协议，以表型心脏瓣膜功能的小鼠。所有的方法和程序，已通过梅奥诊所的机构动物护理和使用委员会。该协议的主要内容包括麻醉深度，心功能的评价，和心脏瓣膜功能的评价。我们希望这份报告不仅有利于引导有兴趣在心脏瓣膜病领域追求研究调查，但也将启动相关协议标准化，以确保在这一快速增长的领域数据的重现性和有效性的国家和国际对话。重要的是，采用高分辨率超声系统成功成像需要的超声（和术语在超声常用）的原理的工作知识，基本的原理与的理解心脏生理学，并用超声显著经验的莱斯以允许在啮齿类动物心脏功能的准确时间效率的评估。
Protocol
Representative Results
Discussion
麻醉诱导
适当的麻醉诱导和维持是在心脏瓣膜小鼠变化的准确评估和心脏功能的关键。由于麻醉的快速诱导异氟醚和以下深度麻醉这一麻醉药的相对较长的洗出时间引起的，我们不使用一个独立的腔麻醉诱导。相反，如在详细说明以上，动物被直接引导至麻醉锥，其允许在相对较低的浓度的麻醉剂的麻醉的快速和受控诱导。
小鼠大多数菌株在…
Disclosures
The authors have nothing to disclose.
Acknowledgements
This work was supported by NIH grants HL111121 (JDM) and TR000954 (JDM).
Materials
| High resolution ultrasound machine | VisualSonics, Fujifilm | Vevo 2100 | |
| Isoflurane diffuser (capable of delivering 1 % to 1.5 % isoflurane mixed with 1 L/min 100% O2 | VisualSonics, Fujifilm | N/A | |
| Transducers for small mice (550D) or larger mice (400) | MicroScan, VisualSonics, Fujifilm | MS 550D, MS 400 | |
| Animal platform | VisualSonics, Fujifilm | 11503 | |
| Advanced physiological monitoring unit | VisualSonics, Fujifilm | N/A | |
| Isoflurane | Terrell | NDC 66794-019-10 | |
| Nose cone and tubing connected to isoflurane diffuser and 100% O2 | Custom Engineered in-house | — | |
| Hair razor | Andis Super AGR+ vet pack clipper | AD65340 | |
| Ultrasound gel | Parker Laboratories | REF 01-08 | |
| Electrode gel | Parker Laboratories | REF 15-25 | |
| Adhesive tapes | Fisher Laboratories | 1590120B | |
| Paper towels |
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