マウスの弁膜症の包括的表現型の特徴のための心エコーアプローチとプロトコル
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
エージングは、心血管石灰化1の漸進的増加と関連しています。血行動態的に重要な大動脈弁狭窄症は、65 2歳以上の人口の3％に影響を及ぼし、さらには中程度の大動脈弁狭窄（3-4メートル/秒のピーク速度）を有する患者は、40％未満の5年無イベント生存率を持っています3。現在、そこに大動脈弁の石灰化の進行を遅らせるために有効な治療法はなく、外科的大動脈弁置換術は、高度な大動脈弁狭窄4のための唯一の可能な治療です。
大動脈弁石灰化の開始および進行に寄与するメカニズムのより深い理解を得ることを目的とした研究は、大動脈弁狭窄5、6を管理するための薬理学的および非外科的方法に向かって移動中の重要な最初のステップです。遺伝学的なLY-変更されたマウスは、種々の疾患に貢献し、今大動脈弁狭窄6、7、8の生物学を理解することを目的とした機構研究の最前線に来ているメカニズムの理解を開発する上で大きな役割を果たしてきました。アテローム性動脈硬化症や心不全、血管および心室機能を評価するための標準プロトコルは大部分がされているような他の心血管疾患とは異なり、マウスにおける心臓弁の機能のin vivoでの表現型に関連付けられている固有の課題は、十分に確立された-があります。最近のレビューは、多数のイメージングおよびげっ歯類9、10、11における弁の機能を評価するために使用侵襲的モダリティの長所と短所についての徹底的な議論を提供してきたが、今日まで、私たちはCOMPREを提供する出版物を認識していませんhensive、マウスでは心臓弁の機能を表現型のためのステップバイステップのプロトコル。
本稿の目的は、マウスにおける心臓弁の機能を表現型にする方法およびプロトコルを記述することです。すべての方法及び手順は、メイヨークリニック制度動物実験委員会によって承認されています。このプロトコルの主な構成要素は、麻酔の深さ、心機能の評価、および心臓弁の機能の評価を含みます。我々は、この報告書は、心臓弁疾患の分野の研究を追求に興味を持って研究者を案内するのに役立つだけでなく、この急速に成長している分野で、データの再現性と妥当性を確保するためのプロトコル標準化に関連する国内および国際的な対話を開始することを願っています。重要なことには、高解像度の超音波システムを使用して成功したイメージングは、基本Principでの理解を加工超音波検査の原理の知識（及び一般的に超音波検査で使用される用語）を必要とレ心臓生理学、およびげっ歯類における心機能の正確かつ時間効率の評価を可能にするために超音波検査での豊富な経験の。
Protocol
Representative Results
Discussion
麻酔導入
適切な麻酔の導入および保守は、マウスの心臓弁の変化の正確な評価や心機能のために重要です。イソフルランによって誘発される麻酔の迅速な誘導と深い麻酔後にこの麻酔薬の比較的長いウォッシュアウト時間を考えると、我々は誘導のために、スタンドアロンの麻酔室を使用しないでください。上記で詳細に述べたように代わりに、動物を麻酔?…
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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