1。準備 1.1。ラットの麻酔<ol><li>ラットを麻酔にイソフルラン（5％の約3分室のサイズに応じて）で予め充填室にラットを置きます。 </li><li>一度麻酔、ラットを取り外して重量を量る。 </li><li>麻酔を維持するために、麻酔マスク（酸素1リットル/分でイソフルラン2〜3％）に、ラットの鼻を置きます。イソフルラン麻酔中に、ラットの心拍数は300から340 BPM（マウスで380-420 BPM）に減少。 </li></ol> 1.2。尾静脈にカニューレを挿入する<ol><li>血管がより簡単に見ることができるように、温水（38℃）と石鹸でラットの尾を洗ってください。 </li><li>簡単に尾の外側面で見ることができるのどちらか静脈を、カニューレを挿入。 22-24 G IVカテーテルを使用して、約1/3の先端から道の試みを開始します。 </li><li>初期の努力が失敗した場合、より近位に再試行します。 </li><li>血SAMを取るヘマトクリットの分析のためのPLE（外体積分率= ECVを計算する必要が）。 </li><li>皮膚接着剤やテープで静脈カテーテルを固定します。 </li></ol> 1.3。電極のポジショニング<ol><li>アルコール飽和綿棒でまたは石鹸と水ですべての足蹠を清掃します。 </li><li>四つの電極は、各足に1つずつ必要とされている。 </li><li>足蹠の中央に電極を取り付け、粘着テープで固定します。 </li><li>ねじれ又はECG信号との干渉を引き起こすループの形成を最小限にするために互いに周りECGケーブルを編む。 </li></ol> 2。スキャニング 2.1。動物とモニタリングの位置付け<ol><li>イメージングチューブに仰臥または腹臥位でラットを置き、位置コイルの中心の心臓。 </li><li>その鼻は（酸素1リットル/分で2〜3％）イソフルラン麻酔を実現コーンにかかっようにラットを配置します。ラットは、息を許可され自由に全体の撮像法を通して。 </li><li>肛門口に温度計のセンサーを置き、テープでテーブルの上にそれを修正する。 </li><li>体温を38±1℃の温水加熱システムによって維持される。加温マットは、コイルの外側に延在動物の下面態様下に置かれる。詳細は、MRI実験（ 図2）の概略図を参照してください。 </li><li> ECG電極を接続し、一度ECG信号は、イメージングを開始し安定しています。 </li></ol> 2.2。スキャンプロトコル/イメージングパラメータ<ol><li>本研究では70ミリメートル、内径とソレノイドコイルとフィリップスインゲニア3.0Tの臨床MRIシステムは、[MRシステム要件は小口径（ 例えば 16センチメートル）または専用の小動物と大口径（人間の大きさ、 例えば 65センチメートル）が使用されました500/min、酸素供給と麻酔ガスの除去システム​​のコイルは、最大心拍数のためのECGゲーティング機能]。 </li><li>ビューのMRI視野の中心に心を見つけるための調査から始まります。 </li><li>位置が正しくなると、短軸画像のスタックの形状を決定するために二室と4室シネMRIの景色を続行します。 </li><li>サリー、二、四室の画像（PreSALLI）上の位置半ば空洞短軸スライス。 4,000ミリ秒の取得時間と4,000ミリ秒の緩和時間の組み合わせは、z軸に沿った磁化を十分に回収を可能にし、勾配の過熱を防止する。機能解析を可能にするために、位相が買収を加速する因子2の時間アンダーで、少なくとも12に設定する必要があります。 </li><li>ラットを動かさずに、留置カテーテルにガドリニウム系造影剤を注入する。 5分待ちます。 </li><li>少なくとも7スライス（スライス厚2.4ミリメートル）で構成される、マルチスライス短軸スタックとしてサリーの計画をスタート。最も遠位の下の心臓とtの頂点になるようにスライスを置き彼のトップレベルは心臓弁にすぐ遠位である。短い軸がセプタムに垂直であることを確認してみてください。ほぼ30分毎（約3サリス）は造影剤の別の投与量を注入する。 </li><li>画像取得が終了したときにスキャナからラットを削除し、麻酔から回復することを可能にする。 </li></ol> 3。画像再構成画像再構成は、専用の画像再構成ツールを使用して、事前定義された再構成パラメータ、またはオフラインを使用してオンラインのどちらかを行ってもよい。 3.1。オンライン復興<ol><li>様々なパラメータを含めて定義することができます。 </li></ol><ul><li>心周期内で再構成ウィンドウの位置と幅（心拍数300/minで収縮期T1マップを達成するために、50〜100ミリ秒からなど ）：T1マッピング用</li><li>再構築された無線する画像の位置と幅反転時間（TI）ウィンドウ番号：IR-準備（LGE）画像用（ 例えば TI 100-300ミリ秒、5枚は、TIS 100-150-200-250-300ミリ秒で5 LGE画像を生成するために）そのウィンドウ薄い。 </li></ul> 3.2。オフライン復興<ol><li>画像再構成のための専用ソフトウェアパッケージ（Gyrotools、チューリッヒ、スイス）を使用する場合は、よりインタラクティブな方法で三組のデータ（シネMR、反転回復とT1マップ）を抽出。 </li><li>収縮末期または対応シネ画像を選択することにより、T1用の拡張末期の定義を調整します。 </li><li>カラーマップとしてT1マップを視覚化する。関心領域の上にマウスを渡すことによって、正確な値を検索します。画像は、さらなる分析（心筋血プールの前後のコントラストT1値からECVの計算など ）12に対して各種画像形式で記憶することができる。 </li></ol>

<ol>
	<li>Messroghli, D. R., Nordmeyer, S., Buehrer, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Small+animal+Look-Locker+inversion+recovery+(SALLI)+for+simultaneous+generation+of+cardiac+T1+maps+and+cine+and+inversion+recovery-prepared+images+at+high+heart+rates:+initial+experience.">Small animal Look-Locker inversion recovery (SALLI) for simultaneous generation of cardiac T1 maps and cine and inversion recovery-prepared images at high heart rates: initial experience.</a> Radiology. 261 (1), 258-2565 (2011).</li><li>Messroghli, D. R., Nordmeyer, S., Dietrich, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+diffuse+myocardial+fibrosis+in+rats+using+small-animal+Look-Locker+inversion+recovery+T1+mapping.">Assessment of diffuse myocardial fibrosis in rats using small-animal Look-Locker inversion recovery T1 mapping.</a> Circ. Cardiovasc. Imaging. 4 (6), 636-640 (2011).</li><li>Flett, A. S., Hayward, M. P., Ashworth, M. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Equilibrium+contrast+cardiovascular+magnetic+resonance+for+the+measurement+of+diffuse+myocardial+fibrosis:+preliminary+validation+in+humans.">Equilibrium contrast cardiovascular magnetic resonance for the measurement of diffuse myocardial fibrosis: preliminary validation in humans.</a> Circulation. 122 (2), 138-144 (2010).</li><li>Arheden, H., Saed, M., Higgins, C. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+the+distribution+volume+of+gadopentetate+dimeglumine+at+echo-planar+MR+imaging+to+quantify+myocardial+infarction:+comparison+with+99mTc-DTPA+autoradiography+in+rats.">Measurement of the distribution volume of gadopentetate dimeglumine at echo-planar MR imaging to quantify myocardial infarction: comparison with 99mTc-DTPA autoradiography in rats.</a> Radiology. 211 (3), 698-708 (1999).</li><li>Messroghli, D. R., Walters, K., Plein, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myocardial+T1+mapping:+application+to+patients+with+acute+and+chronic+myocardial+infarction.">Myocardial T1 mapping: application to patients with acute and chronic myocardial infarction.</a> Magn. Reson. Med. 58 (1), 34-40 (2007).</li><li>O H-Ici, D., Ridgway, J., Kuehne, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiovascular+magnetic+resonance+of+myocardial+edema+using+a+short+inversion+time+inversion+recovery+(STIR)+black-blood+technique:+Diagnostic+accuracy+of+visual+and+semi-quantitative.">Cardiovascular magnetic resonance of myocardial edema using a short inversion time inversion recovery (STIR) black-blood technique: Diagnostic accuracy of visual and semi-quantitative.</a> 14 (1), (2012).</li><li>Sagar, S., Liu, P. P., Cooper, L. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myocarditis.">Myocarditis.</a> Lancet. 379, 738-747 (2012).</li><li>Skouri, H. N., Dec, G. W., Friedrich, M. G., Cooper, L. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noninvasive+imaging+in+myocarditis.">Noninvasive imaging in myocarditis.</a> J. Am. Coll. Cardiol. , 2085-2093 (2006).</li><li>Zagrosek, A., Abdel-Aty, H., Boy&#233;, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+magnetic+resonance+monitors+reversible+and+irreversible+myocardial+injury+in+myocarditis.">Cardiac magnetic resonance monitors reversible and irreversible myocardial injury in myocarditis.</a> JACC Cardiovasc. Imaging. 2 (2), 131-138 (2009).</li><li>Friedrich, M. G., Sechtem, U., Schulz-Menger, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiovascular+magnetic+resonance+in+myocarditis:+a+JACC+White+Paper.">Cardiovascular magnetic resonance in myocarditis: a JACC White Paper.</a> J. Am. Coll. Cardiol. 54, 1475-1487 (2009).</li><li>Korkusuz, H., Esters, P., Naguib, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acute+myocarditis+in+a+rat+model:+late+gadolinium+enhancement+with+histopathological+correlation.">Acute myocarditis in a rat model: late gadolinium enhancement with histopathological correlation.</a> Eur. Radiol. 19 (11), 2672-2678 (2009).</li><li>Ugander, M., Oki, A. J., Hsu, L. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extracellular+volume+imaging+by+magnetic+resonance+imaging+provides+insights+into+overt+and+sub-clinical+myocardial+pathology.">Extracellular volume imaging by magnetic resonance imaging provides insights into overt and sub-clinical myocardial pathology.</a> Eur. Heart J. 33 (10), 1268-1278 (2012).</li><li>Gilson, W. D., Kraitchman, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+magnetic+resonance+imaging+in+small+rodents+using+clinical+1.5.">Cardiac magnetic resonance imaging in small rodents using clinical 1.5.</a> T and. 3 (1), 35-45 (2007).</li><li>Messroghli, D. R., Radjenovic, A., Kozerke, S., Higgins, D. M., Sivananthan, M. U., Ridgway, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modified+Look-Locker+inversion+recovery+(MOLLI)+for+high-resolution+T1+mapping+of+the+heart.">Modified Look-Locker inversion recovery (MOLLI) for high-resolution T1 mapping of the heart.</a> Magnetic resonance in medicine. 52 (1), 141-146 (2004).</li></ol>

全ての動物の手順は、実験動物のケアと使用に関するガイドラインに従って実施され、地元の動物ケアの当局によって承認された。利害の衝突は宣言されていない。

ここでは、小動物のマルチモダリティ（シネMR、反転回復とT1マップ）MR画像を生成する手法を提案する。小動物の研究では、心血管疾患の研究にますます重要な役割を果たしており、CMRは、私たちは、心筋の機能、構造と組織の組成を勉強できるように強力なツールです。しかし、小動物CMRは、高い心拍数と小さな心臓の大きさに起因し固有の課題の数を持っています。より多くの時間効率?...

心筋炎は、急性心不全、突然死、そして慢性的拡張型心筋症7の主要な原因である。 CMRは、関数の測定のためと生体組織の分析でのゴールドスタンダード技術として確立されている。新規イメージング技術とイメージングの改善だけで心筋炎の診断を向上させるだけでなく、治療標的8-10の病態生理と速度同定の研究を支援することができませんでした。小動物イメージングは​​、心血管疾患の研究のための重要なツールです。このような後期ガドリニウム増強（LGE）などの日常臨床CMRで使用される技術は、簡単に動物の高い心拍数に起因する小動物CMRに転送することはできません、しかし、すでに11を示すことができた。小動物ルックロッカー反転回復（サリー）のアプローチは、マルチモーダル画像データを生成し、心機能と形態（ 図1の両方の包括的な評価を可能に設定しますND 3）。ここでは、具体的に、典型的なサリープロトコルで小動物イメージングのための手順とセットアップを示しています。特に、我々は、T1撮像データセットの再構築および分析を示す。

<table border="1">
		<tbody>
		 <tr>
			<td>Name of Reagent/Material</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		 </tr>
		 <tr>
			<td>Adhesive Tape (Silkafix)</td>
			<td>Lohmann und Rauscher</td>
			<td>34327</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Gadopentetat-Dimeglumin (Magnevist)</td>
			<td>Bayer</td>
			<td>G-00012163</td>
			<td>2mmol/Kg</td>
		 </tr>
		 <tr>
			<td>Introcan Safety-W (G24)</td>
			<td>B. Braun</td>
			<td>4254503-01</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Red Dot, Neonatal Monitoring Electrode with Pre-Attached Lead Wire</td>
			<td>3M</td>
			<td>2269T</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Skin glue (Histoacryl)</td>
			<td>B. Braun</td>
			<td>1050052</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Scales (Typ 440)</td>
			<td>Kern</td>
			<td>95088</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Skin desinfection (Softasept N)</td>
			<td>B. Braun Petzold</td>
			<td>360250</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Thermometer </td>
			<td>LumaSense Technologies</td>
			<td>Luxtron 812</td>
			<td></td>
		 </tr>
		</tbody>
 </table>

assessment of cardiac function and myocardial morphology using small animal look-locker inversion recovery (salli) mri in rats

小動物磁気共鳴イメージングは​​、心筋組織における心機能と変化を研究するための重要なツールです。小動物（200から600拍/分）の高い心拍数は、以前CMRイメージングの役割を制限してきた。小動物ルックロッカー反転回復（サリー）は、この問題を克服するための1小動物用T1マッピングシーケンスです。 T1マップは、組織の変化および造影剤の動態に関する定量的情報を提供する。それは、間質性線維症又は浮腫1-6として拡散する心筋プロセスを検出することも可能である。また、画像データの単一のセットから、それが心臓機能とシネと反転回復調製した後期ガドリニウムエンハンスメント型MR画像1を生成することにより心筋瘢痕化を検討することができる。 提示映像は、ステップバイステップの手順が小動物CMRイメージングを実行するために示しています。ここでは、健康のSprague-Dawlが提示されエーラットは、しかし当然それは異なった心臓小動物モデルに拡張することができる。

ここでは、健康のSprague Dawley系ラットからの調査結果を示しています。我々は以前に記載さよく準備された動物の設定と、それは安定したECG信号を取得することが可能である。人間の心臓のMRIプロトコルと同様に、我々は心を見つけるために調査を開始。コイルラットの位置が正しければ、我々は、サリースタックのジオメトリを検出するために、二腔像、四腔像を続行。 <p class="jove_conten...

Watch this Scientific Journal Video about Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery SALLI MRI in Rats at JoVE.com

Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery SALLI MRI in Rats

造影心臓磁気共鳴（CMR）イメージングは​​、包括的なことができます<em生体内で&gt;</em&gt;心血管疾患の小さな動物モデルにおける心臓の評価。ここでは、詳細手順はCMRイメージング、復興とラットの小動物ロックロッカー反転回復（サリー）を使用して分析を実行する。

小動物ルックロッカー反転回復（サリー）ラットにおけるMRIを用いた心機能と心筋形態の評価

Small animal magnetic resonance  imaging is an important tool to study cardiac function and changes in myocardial  tissue. The high heart rates of small ...

assessment-cardiac-function-myocardial-morphology-using-small-animal

Research

JoVE Journal

Medicine

Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery (SALLI) MRI in Rats

12.6K ビュー.  German Heart Institute Berlin. 造影心臓磁気共鳴（CMR）イメージングは​​、包括的なことができます心血管疾患の小さな動物モデルにおける心臓の評価。ここでは、詳細手順はCMRイメージング、復興とラットの小動物ロックロッカー反転回復（サリー）を使用して分析を実行する。

ビデオ: Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery SALLI MRI in Rats

Assessment of Cardiac Function and Energetics in Isolated Mouse Hearts Using 31P NMR Spectroscopy

Bioengineered mouse models have become powerful research tools in determining causal relationships between molecular alterations and models of cardiovascular disease. Although molecular biology is necessary in identifying key changes in the signaling pathway, it is not a surrogate for functional significance. While physiology can provide answers to the question of function, combining physiology with biochemical assessment of metabolites in the intact, beating heart allows for a complete picture of cardiac function and energetics. For years, our laboratory has utilized isolated heart perfusions combined with nuclear magnetic resonance (NMR) spectroscopy to accomplish this task. Left ventricular function is assessed by Langendorff-mode isolated heart perfusions while cardiac energetics is measured by performing 31P magnetic resonance spectroscopy of the perfused hearts. With these techniques, indices of cardiac function in combination with levels of phosphocreatine and ATP can be measured simultaneously in beating hearts. Furthermore, these parameters can be monitored while physiologic or pathologic stressors are instituted. For example, ischemia/reperfusion or high workload challenge protocols can be adopted. The use of aortic banding or other models of cardiac pathology are apt as well. Regardless of the variants within the protocol, the functional and energetic significance of molecular modifications of transgenic mouse models can be adequately described, leading to new insights into the associated enzymatic and metabolic pathways. Therefore, 31P NMR spectroscopy in the isolated perfused heart is a valuable research technique in animal models of cardiovascular disease.

Assessment of Cardiac Function and Energetics in Isolated Mouse Hearts Using 31P NMR Spectroscopy

Langendorff-mode isolated heart perfusion, in conjunction with 31P NMR spectroscopy, combines the fields of biochemistry and physiology into one experiment. The protocol allows for the dynamic measurement of high energy phosphate content and turnover in the heart while concurrently monitoring physiologic function. When performed correctly, this is a valuable technique in the assessment of cardiac energetics.

使用する絶縁マウスハーツの心機能およびエネルギー論の評価 31 P NMR分光法

Bioengineered mouse models have become powerful research tools in determining causal relationships between molecular alterations and models of ...

医学

Acute Myocardial Infarction in Rats

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular diseases. Animal models that mimic human cardiac disease, such as myocardial infarction (MI) and ischemia-reperfusion (IR) that induces heart failure as well as pressure-overload (transverse aortic constriction) that induces cardiac hypertrophy and heart failure (Goldman and Tarnavski), are useful models to study cardiovascular disease. In particular, myocardial ischemia (MI) is a leading cause for cardiovascular morbidity and mortality despite controlling certain risk factors such as arteriosclerosis and treatments via surgical intervention (Thygesen). Furthermore, an acute loss of the myocardium following myocardial ischemia (MI) results in increased loading conditions that induces ventricular remodeling of the infarcted border zone and the remote non-infarcted myocardium. Myocyte apoptosis, necrosis and the resultant increased hemodynamic load activate multiple biochemical intracellular signaling that initiates LV dilatation, hypertrophy, ventricular shape distortion, and collagen scar formation. This pathological remodeling and failure to normalize the increased wall stresses results in progressive dilatation, recruitment of the border zone myocardium into the scar, and eventually deterioration in myocardial contractile function (i.e. heart failure). The progression of LV dysfunction and heart failure in rats is similar to that observed in patients who sustain a large myocardial infarction, survive and subsequently develops heart failure (Goldman). The acute myocardial infarction (AMI) model in rats has been used to mimic human cardiovascular disease; specifically used to study cardiac signaling mechanisms associated with heart failure as well as to assess the contribution of therapeutic strategies for the treatment of heart failure. The method described in this report is the rat model of acute myocardial infarction (AMI). This model is also referred to as an acute ischemic cardiomyopathy or ischemia followed by reperfusion (IR); which is induced by an acute 30-minute period of ischemia by ligation of the left anterior descending artery (LAD) followed by reperfusion of the tissue by releasing the LAD ligation (Vasilyev and McConnell). This protocol will focus on assessment of the infarct size and the area-at-risk (AAR) by Evan's blue dye and triphenyl tetrazolium chloride (TTC) following 4-hours of reperfusion; additional comments toward the evaluation of cardiac function and remodeling by modifying the duration of reperfusion, is also presented. Overall, this AMI rat animal model is useful for studying the consequence of a myocardial infarction on cardiac pathophysiological and physiological function.

The rat model of acute myocardial infarction (AMI) is useful to study the consequence of a MI on cardiac pathophysiological and physiological function.

ラットにおける急性心筋梗塞

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular ...

MRI and PET in Mouse Models of Myocardial Infarction

Myocardial infarction is one of the leading causes of death in the Western world. The similarity of the mouse heart to the human heart has made it an ideal model for testing novel therapeutic strategies.
In vivo magnetic resonance imaging (MRI) gives excellent views of the heart noninvasively with clear anatomical detail, which can be used for accurate functional assessment. Contrast agents can provide basic measures of tissue viability but these are nonspecific. Positron emission tomography (PET) is a complementary technique that is highly specific for molecular imaging, but lacks the anatomical detail of MRI. Used together, these techniques offer a sensitive, specific and quantitative tool for the assessment of the heart in disease and recovery following treatment.
In this paper we explain how these methods are carried out in mouse models of acute myocardial infarction. The procedures described here were designed for the assessment of putative protective drug treatments. We used MRI to measure systolic function and infarct size with late gadolinium enhancement, and PET with fluorodeoxyglucose (FDG) to assess metabolic function in the infarcted region. The paper focuses on practical aspects such as slice planning, accurate gating, drug delivery, segmentation of images, and multimodal coregistration. The methods presented here achieve good repeatability and accuracy maintaining a high throughput.

We describe how to perform MRI and PET imaging of the mouse heart. The protocol is tailored to assess treatment efficacy in models of myocardial infarction and heart failure.

Myocardial infarction is one of the leading causes of death in the Western world. The similarity of the mouse heart to the human heart has made it an ...

Ascending Aortic Constriction in Rats for Creation of Pressure Overload Cardiac Hypertrophy Model

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart failure. Here, we describe a detailed surgical procedure for creating pressure overload and cardiac hypertrophy in rats by constriction of the ascending aorta using a small metallic clip. After anesthesia, the trachea is intubated by inserting a cannula through a half way incision made between two cartilage rings of trachea. Then a skin incision is made at the level of the second intercostal space on the left chest wall and muscle layers are cleared to locate the ascending portion of aorta. The ascending aorta is constricted to 50&#8211;60% of its original diameter by application of a small sized titanium clip. Following aortic constriction, the second and third ribs are approximated with prolene sutures. The tracheal cannula is removed once spontaneous breathing was re-established. The animal is allowed to recover on the heating pad by gradually lowering anesthesia. The intensity of pressure overload created by constriction of the ascending aorta is determined by recording the pressure gradient using trans-thoracic two dimensional Doppler-echocardiography. Overall this protocol is useful to study the remodeling events and contractile properties of the heart during the gradual onset and progression from compensated cardiac hypertrophy to heart failure stage.

We describe a stepwise procedure for creating pressure overload and left ventricular hypertrophy in Wistar rats by constriction of the ascending aorta using a small metallic clip. This model is extensively used for studying remodeling changes during cardiac hypertrophy and for identifying and evaluating strategies for regression of such changes.

圧負荷心肥大モデルの作成のためのラットの大動脈狭窄昇順

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart ...

Assessment of Right Ventricular Structure and Function in Mouse Model of Pulmonary Artery Constriction by Transthoracic Echocardiography

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, the RV is significantly affected in pulmonary diseases such as pulmonary artery hypertension (PAH). In addition, the RV is remarkably sensitive to cardiac pathologies, including left ventricular (LV) dysfunction, valvular disease or RV infarction4. To understand the role of RV in the pathogenesis of cardiac diseases, a reliable and noninvasive method to access the RV structurally and functionally is essential.
A noninvasive trans-thoracic echocardiography (TTE) based methodology was established and validated for monitoring dynamic changes in RV structure and function in adult mice. To impose RV stress, we employed a surgical model of pulmonary artery constriction (PAC) and measured the RV response over a 7-day period using a high-frequency ultrasound microimaging system. Sham operated mice were used as controls. Images were acquired in lightly anesthetized mice at baseline (before surgery), day 0 (immediately post-surgery), day 3, and day 7 (post-surgery). Data was analyzed offline using software.
Several acoustic windows (B, M, and Color Doppler modes), which can be consistently obtained in mice, allowed for reliable and reproducible measurement of RV structure (including RV wall thickness, end-diastolic&#160;and end-systolic dimensions), and function (fractional area change, fractional shortening, PA peak velocity, and peak pressure gradient) in normal mice and following PAC.
Using this method, the pressure-gradient resulting from PAC was accurately measured in real-time using Color Doppler mode and was comparable to direct pressure measurements performed with a Millar high-fidelity microtip catheter. Taken together, these data demonstrate that RV measurements obtained from various complimentary views using echocardiography are reliable, reproducible and can provide insights regarding RV structure and function. This method will enable a better understanding of the role of RV cardiac dysfunction.

Right ventricle (RV) dysfunction is critical to the pathogenesis of cardiovascular disease, yet limited methodologies are available for its evaluation. Recent advances in ultrasound imaging provide a noninvasive and accurate option for longitudinal RV study. Herein, we detail a step-by-step echocardiographic method using a murine model of RV pressure overload.

経胸壁心エコー検査による肺動脈狭窄のマウスモデルにおける右室の構造と機能の評価

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, ...

Echocardiographic and Histological Examination of Cardiac Morphology in the Mouse

An increasing number of genetically modified mouse models has become available in recent years. Moreover, the number of pharmacological studies performed in mice is high. Phenotypic characterization of these mouse models also requires the examination of cardiac function and morphology. Echocardiography and magnetic resonance imaging (MRI) are commonly used approaches to characterize cardiac function and morphology in mice. Echocardiographic and MRI equipment specialized for use in small rodents is&#160;expensive and requires a dedicated space. This protocol describes cardiac measurements in mice using a clinical echocardiographic system with a 15 MHz human vascular probe. Measurements are performed on anesthetized adult mice. At least three image sequences are recorded and analyzed for each animal in M-mode in the parasternal short-axis view. Afterwards, cardiac histological examination is performed, and cardiomyocyte diameters are determined on hematoxylin-eosin- or wheat germ agglutinin (WGA)-stained paraffin sections. Vessel density is determined morphometrically after Pecam-1 immunostaining. The protocol has been applied successfully to pharmacological studies and different genetic animal models under baseline conditions, as well as after experimental myocardial infarction by the permanent ligation of the left anterior descending coronary artery (LAD). In our experience, echocardiographic investigation is limited to anesthetized animals and is feasible in adult mice weighing at least 25 g.

Echocardiographic examination is frequently used in mice. Expensive high-resolution ultrasound devices have been developed for this purpose. This protocol describes an affordable echocardiographic procedure combined with histological morphometric analyses to determine cardiac morphology.

マウスの心臓形態の心エコー検査・組織学的検討

An increasing number of genetically modified mouse models has become available in recent years. Moreover, the number of pharmacological studies performed ...

In Vivo Evaluation of Fracture Callus Development During Bone Healing in Mice Using an MRI-compatible Osteosynthesis Device for the Mouse Femur

Endochondral fracture healing is a complex process involving the development of fibrous, cartilaginous, and osseous tissue in the fracture callus. The amount of the different tissues in the callus provides important information on the fracture healing progress. Available in vivo techniques to longitudinally monitor the callus tissue development in preclinical fracture-healing studies using small animals include digital radiography and &#181;CT imaging. However, both techniques are only able to distinguish between mineralized and non-mineralized tissue. Consequently, it is impossible to discriminate cartilage from fibrous tissue. In contrast, magnetic resonance imaging (MRI) visualizes anatomical structures based on their water content and might therefore be able to noninvasively identify soft tissue and cartilage in the fracture callus. Here, we report the use of an MRI-compatible external fixator for the mouse femur to allow MRI scans during bone regeneration in mice. The experiments demonstrated that the fixator and a custom-made mounting device allow repetitive MRI scans, thus enabling longitudinal analysis of fracture-callus tissue development.

In Vivo Evaluation of Fracture Callus Development During Bone Healing in Mice Using an MRI-compatible Osteosynthesis Device for the Mouse Femur

The evaluation of tissue development in the fracture callus during endochondral bone healing is essential to monitor the healing process. Here, we report the use of a magnetic resonance imaging (MRI)-compatible external fixator for the mouse femur to allow MRI scans during bone regeneration in mice.

生体内で破壊カルス開発マウス大腿骨の骨、MRI 対応のデバイスを用いたマウスの骨治癒過程の評価

Endochondral fracture healing is a complex process involving the development of fibrous, cartilaginous, and osseous tissue in the fracture callus. The ...

Normothermic Ex Situ Heart Perfusion in Working Mode: Assessment of Cardiac Function and Metabolism

The current standard method for organ preservation (cold storage, CS), exposes the heart to a period of cold ischemia that limits the safe preservation time and increases the risk of adverse post-transplantation outcomes. Moreover, the static nature of CS does not allow for organ evaluation or intervention during the preservation interval. Normothermic ex situ heart perfusion (ESHP) is a novel method for preservation of the donated heart that minimizes cold ischemia by providing oxygenated, nutrient-rich perfusate to the heart. ESHP has been shown to be non-inferior to CS in the preservation of standard-criteria donor hearts and has also facilitated the clinical transplantation of the hearts donated after the circulatory determination of death. Currently, the only available clinical ESHP device perfuses the heart in an unloaded, non-working state, limiting assessments of myocardial performance. Conversely, ESHP in working mode provides the opportunity for comprehensive evaluation of cardiac performance by assessment of functional and metabolic parameters under physiologic conditions. Moreover, earlier experimental studies have suggested that ESHP in working mode may result in improved functional preservation. Here, we describe the protocol for ex situ perfusion of the heart in a large mammal (porcine) model, which is reproducible for different animal models and heart sizes. The software program in this ESHP apparatus allows for real-time and automated control of the pump speed to maintain desired aortic and left atrial pressure and evaluates a variety of functional and electrophysiological parameters with minimal need for supervision/manipulation.

Normothermic ex situ heart perfusion (ESHP), preserves the heart in a beating, semi-physiologic state. When performed in a working mode, ESHP provides the opportunity to perform sophisticated assessments of donor heart function and organ viability. Here, we describe our method for myocardial performance evaluation during ESHP.

常温動作モードの場心の灌流 Ex: 心機能と代謝の評価

The current standard method for organ preservation (cold storage, CS), exposes the heart to a period of cold ischemia that limits the safe preservation ...

Continuous Blood Sampling in Small Animal Positron Emission Tomography/Computed Tomography Enables the Measurement of the Arterial Input Function

For quantitative analysis and bio-kinetic modeling of positron emission tomography/computed tomography (PET/CT) data, the determination of the temporal blood time-activity concentration also known as arterial input function (AIF) is a key point, especially for the characterization of animal disease models and the introduction of newly developed radiotracers. The knowledge of radiotracer availability in the blood helps to interpret PET/CT-derived data of tissue activity. For this purpose, online blood sampling during the PET/CT imaging is advisable to measure the AIF. In contrast to manual blood sampling and image-derived approaches, continuous online blood sampling has several advantages. Besides the minimized blood loss, there is an improved resolution and a superior accuracy for the blood activity measurement. However, the major drawback of online blood sampling is the costly and time-consuming preparation to catheterize the femoral vessels of the animal. Here, we describe an easy and complete workflow for catheterization and continuous blood sampling during small animal PET/CT imaging and compared it to manual blood sampling and an image-derived approach. Using this highly-standardized workflow, the determination of the fluorodeoxyglucose ([18F]FDG) AIF is demonstrated. Further, this procedure can be applied to any radiotracer in combination with different animal models to create fundamental knowledge of tracer kinetic and model characteristics. This allows a more precise evaluation of the behavior of pharmaceuticals, both for diagnostic and therapeutic approaches in the preclinical research of oncological, neurodegenerative and myocardial diseases.

Here a protocol for continuous blood sampling during PET/CT imaging of rats to measure the arterial input function (AIF) is described. The catheterization, the calibration and setup of the system and the data analysis of the blood radioactivity are demonstrated. The generated data provide input parameters for subsequent bio-kinetic modeling.

小動物陽電子放出断層撮影/コンピュータ断層撮影における連続的な血液サンプリングにより、動脈入力機能の測定が可能

For quantitative analysis and bio-kinetic modeling of positron emission tomography/computed tomography (PET/CT) data, the determination of the temporal ...

Echocardiographic Assessment of Cardiac Anatomy and Function in Adult Rats

The use of experimental animal models has become crucial in cardiovascular science. Most studies using rodent models are focused on two-dimensional imaging to study the cardiac anatomy of the left ventricle and M-mode echo to assess its dimensions. However, this could limit a comprehensive study. Herein, we describe a protocol that allows an assessment of the heart chamber size, left ventricular function (systolic and diastolic) and valvular function. A conventional medical ultrasound machine was used in this protocol and different echo views were obtained through left parasternal, apical and suprasternal windows. In the left parasternal window, the long and short axis were acquired to analyze left chamber dimensions, right ventricle and pulmonary artery dimensions, and mitral, pulmonary and aortic valve function. The apical window allows the measurement of heart chamber dimensions and evaluation of systolic and diastolic parameters. It also allows Doppler assessment with detection and quantification of heart valve disturbances (regurgitation or stenosis). Different segments and walls of the left ventricle are visualized throughout all views. Finally, the ascending aorta, aortic arch, and descending aorta can be imaged through the suprasternal window. A combination of ultrasound imaging, Doppler flow and tissue Doppler assessment have been obtained to study cardiac morphology and function. This represents an important contribution to improve the assessment of cardiac function in adult rats with impact for research using these animal models.

A non-invasive protocol for transthoracic echocardiography assessment of cardiac anatomy and function for adult rats is presented in the current study. The heart valves, all four cardiac chambers and the ascending aorta, aortic arch and descending aorta are studied in detail.

成人ラットにおける心臓解剖学と機能の心エコー評価

The use of experimental animal models has become crucial in cardiovascular science. Most studies using rodent models are focused on two-dimensional ...