我々は博士エリオサルガド、レナータLataroとマウロ·デ·オリベイラ、設定プロセス中に寛大な支援のためのリベイラウンプレト、サンパウロ、博士ベンヤンセン、心臓血管研究所マーストリヒト、マーストリヒト大学、大学の医学部に感謝します。 この作品は、SDCにFONDECYT助成N°11090114によってサポートされていました

プロトコルはAlemana-ティコ大学Desarrollo FacultadデMedicinaのクリニカの倫理委員会によって承認された。 I.はドブタミン投与の準備<ol><li> 500μg/ mlのドブタミンの原液を得るために、滅菌蒸留水20mlにドブタミン10mgを溶解します。 -20℃でアリコートとストアこのソリューションは、3ヶ月間、少なくとも使用することができます。 </li><li>室温でドブタミンストック溶液のアリコートを解凍します。 </li><li>ドブタミン（μg/ ​​ml）を=体重X 0.2：計算式を用いて算出される濃度ドブタミン実用的なソリューションを得るためには、滅菌0.9％NaCl中ドブタミン原液を希釈します。 </li><li>ドブタミン作業溶液で1 mlシリンジ29Gx1 / 2 &quot;を記入してください。 </li><li> 20センチメートルPE-10チューブに注射器の針を挿入します。 </li><li>メーカーの指示に従って、輸液ポンプ、シリンジを調整します。 </li><li>ステップでランプ注入を設定6つのステップでは、ステップごとに10μl/分の増加に伴って形式をツーステップ実行します。 </li></ol> Ⅱ。圧力センサの準備<ol><li>少なくとも15分間37℃で滅菌水における信号ドリフト、水没圧力センサを最小限に抑えます。その静水圧が圧力センサに影響を与えないようにするために、0.5以上cm深いカテーテルを浸してはいけません。 </li><li>電子的に25〜100 mmHgの時に圧力センサーのキャリブレーションを行います。電気入力（ボルト）が圧力信号（mmHg）のに変換されます。 </li><li> 2 K / sのサンプリング·レートを設定し、100 Hzのカットオフでローパスフィルタを使用しています。ゼロmmHgに圧力信号を設定します。 </li><li>先端からカテーテル15ミリメートルをマークします。導入ポイントから心臓に到達することは遠い左ventriculeにカテーテルの存在を検出し、心エコー検査により推定した。 </li></ol> Ⅲ。カテーテル検査のためにマウスを準備する<ol><li>重量のC57BL / 6雄マウス、30から32週齢。 </li><li>腹腔内に60μg/ kgのケタミンと4μg/ kgのキシラジン1を注入します 。注：その他の麻酔薬は、例えば、使用されるかもしれません：350から450μg/ kgのAVERTIN、ペントバルビタールまたは1.5 50μg/ kgの- 2％イソフルレン2-3。 </li><li>電気かみそりで首を剃る。 </li><li>暖められた等温加熱プレート上に仰臥位で麻酔マウスを置きます。紙テープとその手足を固定します。 </li><li>完全鎮静状態を確認するためにつま先のピンチを実行します。 </li><li>穏やかに体温を監視するために直腸プローブを挿入します。 vaselinizedプローブを使用することをお勧めします。 </li><li>体温が37から異なる場合℃±0.5℃、加熱板を介してそれを調整してください。 </li><li>酸素供給の近くにマウスの鼻を入れてください。 </li><li>実体顕微鏡下でマウスの頸部領域に配置します。 </li></ol> Ⅳ。データ収集<ol><li> LabChartPro 7ソフトウェアでは、圧力登録および心拍数（HR）の1チャネルごとに1つのチャネルを選択する登録。後者については、オプションの &quot;巡回測定&quot;やレートなどのセットアップの測定を選択します。 </li><li> 0から150 mmHgの圧力：チャネルのスケール範囲を設定します。 </li><li> 200から600 BPM：人事チャンネル、スケール範囲を設定してください。 </li><li>登録を開始し、スタートキーを押します。 </li><li>例えば実行手順を示すコメントを挿入：麻酔の投与は、変更を呼吸し、ドブタミン投与、ドブタミン濃度の開始。 </li></ol> 4,5 Vの心臓カテーテル検査<ol><li>顎付近の右側に小さな切開を行います。ハサミで皮膚、筋肉、結合組織を分離します。 </li><li>気管の右側にある - 縦郭清（2センチメートル1.5）を実行します。気管の近くに右頸動脈を露出させるために、湾曲したピンセットで結合組織、脂肪と筋肉を分離する。 </li><li>頸動脈を露出させるために動物右側にパンダを置きます。脈打つ心臓によって発生した圧力は、動脈の同定を容易にする。暗赤色である頸静脈は、右側にあります。 </li><li>湾曲したピンセットで隣接組織から動脈を分離します。白い糸に似ている迷走神経は、動脈に沿って位置しています</li><li> 6/0絹糸と、それを &quot;二重&quot;の20cmの部分を切り取ります。 </li><li>左から右への動脈の下に &quot;二重&quot;のスレッドを渡します。別の端を得るために、スレッドをカット。 </li><li>動脈下の3番目のスレッド（10センチ）を渡します。 </li><li>頭の近くに位置してスレッド、より遠位の糸が緩んでいない1でタイトな結び目を作る。 </li><li>真ん中のスレッドで緩い結び目を作る、紙のテープで加熱パッドの真ん中のスレッドの右端に固定してください。 </li><li>滅菌0.9％NaClをドロップすることにより、頸動脈の潤いを保つ。綿棒で液体の過剰をふいて乾かす。 </li><li>止血クランプで下糸を伸ばす。 </li><li> pによって止血はさみの位置を固定する血流を閉塞するために、上糸を伸ばし、腹部の皮膚をインチング。動脈周囲の結合組織が削除されていることを確認します。動脈は血液の完全かつパルスを奪わなければなりません。動脈のトルク力を発生させるからスレッドを防ぐ。 </li><li> Vannasマイクロシザーと動脈の下部付近断面ニックネームを作成します。血滴がこぼれされます。 </li><li>頸動脈にカテーテルを挿入します。全体の圧力センサーを導入するようにしてください。は血液の損失がないことを確認します。 </li><li>優しく場所にカテーテルを保持するために、中央の糸の結び目を調整します。あまりにも圧縮されません、圧力センサは、非常に壊れやすいです。 </li><li>動物の腹部から止血はさみを放します。 </li><li>血液の損失を避けるために、手でカテーテルを保持し、真ん中のスレッドを押し込みます。注意：動脈が血でいっぱいにする必要があります。 </li><li>記録圧力信号を開始します。 </li><li>カテーテルが内側にある場合には、動脈圧の信号が60から70 100から120 mmHgに変動します。圧力信号の形状は、 図1.A.ノートで示されています：あなたがオンに興味を持っている場合、信号が少なくとも5分間安定していれば、この時点では、動脈圧を記録することができます。 HRの値は、記録信号の30秒の間隔を考慮した圧力波形から得られた。これは、調査の目標に応じて、人事の直接測定のためにも、心電図の方法を用いることができる。 </li><li>優しく圧力信号（ 図1.B）の形状の変化を観察するためにカテーテルを押し上げる。カテーテルは左心室の内側になると、圧力信号は0 100から120 mmHgに変動します。それはカテーテルをスライドさせることが困難な場合は、2本の指で動物の胸をつまむ。 </li><li>継続的に呼吸数、体温、麻酔レベルと圧力信号を制御します。それらのすべてが安定している必要があります。 </li></ol> Ⅵ。ドブタミンの点滴<ol><li&gt;頚静脈カニュレーションの場合、その穿孔を防ぐために、静脈の周りに戻って皮脂肪組織に確認してください。静脈閉塞のための外科的処置は、頸動脈のために示した手順と同様です。 </li><li>静脈内に、PE-10チューブをご紹介します。血流が後方シリンジのプランジャーを動かすブロックされていないことを確認します。 </li><li>ドブタミン投与は10μl/分で開始し、60μl/分で仕上げてください。すべての工程において、注入速度は2分6のために維持されます。 </li><li>最後ドブタミンの投与後、麻酔の過剰投与で動物を安楽死させる。 </li></ol> Ⅶ。データ解析<ol><li>データ解析のために、あなたの興味のある記録データのセクションを選択します。圧力信号が安定している場所の時間間隔を考慮してください。 </li><li>血圧モジュールのセットアップ]アイコンを選択します。圧力信号の選択されたタイプを示しています。 </li><li>自動的にLabChartPro 7ソフトウェアが表示されたら意味、最大人事、収縮期血圧（P max）は、拡張期血圧（P 分 ）、拡張末期圧（EDP）、最大正圧開発（DP / dtmax）および最大負圧開発（dP / dtのmin）の値と最小値。また、心臓のパラメータが圧力トレースに描写することができます。 </li></ol>

<ol>
	<li>Hart, C. Y., Burnett, J. C., Redfield, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+avertin+versus+xylazine-ketamine+anesthesia+on+cardiac+function+in+normal+mice.">Effects of avertin versus xylazine-ketamine anesthesia on cardiac function in normal mice.</a> Am. J. Physiol. Heart Circ. Physiol. 281, H1938-H1945 (2001).</li><li>Janssen, B. 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=Effects+of+anesthetics+on+systemic+hemodynamics+in+mice.">Effects of anesthetics on systemic hemodynamics in mice.</a> Am. J. Physiol. Heart Circ. Physiol. 287, H1618-H1624 (2004).</li><li>Lorenz, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+practical+guide+to+evaluating+cardiovascular,+renal,+and+pulmonary+function+in+mice.">A practical guide to evaluating cardiovascular, renal, and pulmonary function in mice.</a> Am. J. Physiol. Regul. Integr. Comp. Physiol. 282, R1565-R1582 (2002).</li><li>Lorenz, J. N., Robbins, J. <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+intraventricular+pressure+and+cardiac+performance+in+the+intact+closed-chest+anesthetized+mouse.">Measurement of intraventricular pressure and cardiac performance in the intact closed-chest anesthetized mouse.</a> Am. J. Physiol. 272, H1137-H1146 (1997).</li><li>Nemoto, S., DeFreitas, G., Carabello, B. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+catheterization+technique+in+a+closed-chest+murine+model.">Cardiac catheterization technique in a closed-chest murine model.</a> Contemp. Top. Lab Anim. Sci. 42, 34-38 (2003).</li><li>Daniels, A., 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=Impaired+cardiac+functional+reserve+in+type+2+diabetic+db/db+mice+is+associated+with+metabolic,+but+not+structural,+remodelling.">Impaired cardiac functional reserve in type 2 diabetic db/db mice is associated with metabolic, but not structural, remodelling.</a> Acta Physiol. (Oxf). 200, 11-22 (2010).</li><li>De Celle, 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=Long-term+structural+and+functional+consequences+of+cardiac+ischaemia-reperfusion+injury+in+vivo+in+mice.">Long-term structural and functional consequences of cardiac ischaemia-reperfusion injury in vivo in mice.</a> Exp. Physiol. 89, 605-615 (2004).</li><li>Huntgeburth, 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=Transforming+growth+factor+beta+oppositely+regulates+the+hypertrophic+and+contractile+response+to+beta-adrenergic+stimulation+in+the+heart.">Transforming growth factor beta oppositely regulates the hypertrophic and contractile response to beta-adrenergic stimulation in the heart.</a> PLoS One. 6, e26628 (2011).</li><li>Reddy, A. K., 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+function+in+young+and+old+Little+mice.">Cardiac function in young and old Little mice.</a> J. Gerontol. A. Biol. Sci. Med. Sci. 62, 1319-1325 (2007).</li><li>Christoffersen, C., 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+lipid+accumulation+associated+with+diastolic+dysfunction+in+obese+mice.">Cardiac lipid accumulation associated with diastolic dysfunction in obese mice.</a> Endocrinology. 144, 3483-3490 (2003).</li></ol>

特別な利害関係は宣言されません。

ドブタミンにより誘導され、心臓カテーテル検査によって監視心臓ストレステストは面倒である。それにもかかわらず、プロトコルに従うと、ここで説明するとトレーニングの短い時間で、それは最後の約1時間、その単一の実験で6血行動態パラメータを評価することが可能です。 ここに提示されたプロトコルの重要なステップは、血管のcannulationsです。頸動脈のカニュ...

<table border="1"><tbody><tr><td></td><td></td><td></td><td> 試薬 </td></tr><tr><td> PE-50/10 </td><td>ワーナー·インスツルメンツ</td><td> 64から0752 </td><td></td></tr><tr><td>絹糸6/0 HR17 </td><td> Tagum </td><td> SN0713K </td><td></td></tr><tr><td> Xylacin 20 mg / mlの</td><td>ラボラトリのCentrovet </td><td></td><td></td></tr><tr><td>ケタミン100 mg / mlの</td><td>ドラッグファーマ</td><td></td><td></td></tr><tr><td>塩化ナトリウム0.9パーセント</td><td>ラボサンダーソンのSA </td><td></td><td></td></tr><tr><td>塩酸ドブタミン</td><td>シグマアルドリッチ</td><td> D0676 </td><td></td></tr><tr><td>注射器U-100のインスリン29G X½ &quot; </td><td>テルモメディカル株式会社</td><td></td><td></td></tr><tr><td>マイクロ11.5cmのスタイル7の解剖鉗子</td><td>ロートンMedizintechnik </td><td> 09から0959 </td><td></td></tr><tr><td>グレーフェ鉗子CVD 0.7ミリメートル7センチメートル</td><td>ロートンMedizintechnik </td><td> 62から0263 </td><td></td></tr><tr><td>クランプディーフェンバハブルドッグClでのStr 38ミリメートル</td><td>ロートンMedizintechnik </td><td> 60から010 </td><td></td></tr><tr><td> Vannasはさみ8センチメートル筋力Fhの</td><td>ロートンMedizintechnik </td><td> 63から1400 </td><td></td></tr><tr><td></td><td></td><td></td><td> 機器 </td></tr><tr><td> SPR-671-ミクロ先端圧力カテーテル</td><td>ミラー楽器</td><td> 840-6719 </td><td></td></tr><tr><td> PCU-2000圧力制御ユニット</td><td>ミラー楽器</td><td> 880-0129 </td><td></td></tr><tr><td> PowerLabの4月30日</td><td> ADinstruments Pty Ltdの</td><td> ML866 </td><td></td></tr><tr><td> LabChartPro 7 </td><td> ADinstruments Pty Ltdの</td><td> MLU260 / 7 </td><td></td></tr><tr><td> Legato200輸液ポンプ</td><td> KdScientific </td><td> KD-KDS210P </td><td></td></tr><tr><td> TCAT-2LV温度コントローラと等温加熱板</td><td> PhysiTempインスツルメンツ株式会社</td><td></td><td></td></tr><tr><td>医療用酸素供給</td><td> Indura </td><td></td><td></td></tr><tr><td>直腸プローブ</td><td> ADinstruments Pty Ltdの</td><td> MLT1404 </td><td></td></tr><tr><td>三眼顕微鏡、軸方向の照明</td><td> LW科学</td><td> Z2B-TRI-ETNE、ILP-1502-LTS1、ILP-1502-DGGF </td><td></td></tr></tbody></table>

cardiac stress test induced by dobutamine and monitored by cardiac catheterization in mice

ドブタミンは、動脈（β2）で発現する受容体よりも心（β1）に発現した受容体に対して高い親和性を有するβ-アドレナリン受容体アゴニストである。全身的に投与する場合は、心臓の需要を増加させます。したがって、ドブタミンは、心筋梗塞のリスクが潜在的に異常なリズムや虚血領域のマスクを解除。 心臓ストレステスト中に心機能のモニタリングがecocardiographyまたは心臓カテーテル検査のいずれかによって行うことができます。後者は前者、その侵襲性がより正確かつ有益な手法である。 心拍数（HR）、収縮期血圧、拡張期血圧、拡張終期圧、最大正圧：心臓ストレステストドブタミンによって誘導され、ここで説明したように達成心臓カテーテル検査によって監視は、単一の実験では、以下の血行動態パラメータの測定では、でき開発（DP / dtmax）および最大否定的な報道URE開発（dP / dtの分 ）、ベースライン条件でとドブタミンの漸増用量の下で。 予想されたように、正常マウスで我々は、HR、dP / dtの最大値およびdP / dtの分でドブタミン用量依存性の増加を観察した。また、試験した最高用量（12 ng / gの/ min）で高脂肪食餌誘導性肥満マウスの心臓の代償不全がアンマスクされました。

動脈圧信号は収縮期血圧と拡張期血圧で定義されています。圧力センサは、左心室の内側にある場合には、その圧力（LVP）波形は拡張期血圧と心室収縮（ 図1）の前に左心房収縮の出現にゼロに低下することを特徴とする。ベースライン状態、ケタミン-キシラジン麻酔下正常マウスで280のHRを持っていた±24、107のP 最大 ±8、5のP 分 ±1、14のEDP±2、6081のdP / dtの...

Watch this Scientific Journal Video about Cardiac Stress Test Induced by Dobutamine and Monitored by Cardiac Catheterization in Mice at JoVE.com

Cardiac Stress Test Induced by Dobutamine and Monitored by Cardiac Catheterization in Mice

我々はドブタミンにより誘導され、正常マウスにおける心臓カテーテル検査によって監視心臓ストレステストを実行するためのプロトコルを記述します。また、我々は、高脂肪食誘発肥満マウスでは無症候性心疾患のマスクを解除するために、そのアプリケーションを示しています。

心臓ストレステストドブタミンによって誘導され、マウスにおける心臓カテーテル検査によって監視される

Dobutamine is a &beta;-adrenergic agonist with an affinity higher for receptor expressed in the heart (&beta;1) than for receptors expressed in the ...

cardiac-stress-test-induced-dobutamine-monitored-cardiac

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17.9K ビュー.  Clínica Alemana Universidad del Desarrollo. 我々はドブタミンにより誘導され、正常マウスにおける心臓カテーテル検査によって監視心臓ストレステストを実行するためのプロトコルを記述します。また、我々は、高脂肪食誘発肥満マウスでは無症候性心疾患のマスクを解除するために、そのアプリケーションを示しています。

ビデオ: Cardiac Stress Test Induced by Dobutamine and Monitored by Cardiac Catheterization in Mice

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, ...

医学

Noninvasive Assessment of Cardiac Abnormalities in Experimental Autoimmune Myocarditis by Magnetic Resonance Microscopy Imaging in the Mouse

Myocarditis is an inflammation of the myocardium, but only ~10% of those affected show clinical manifestations of the disease. To study the immune events of myocardial injuries, various mouse models of myocarditis have been widely used. This study involved experimental autoimmune myocarditis (EAM) induced with cardiac myosin heavy chain (Myhc)-&#945; 334-352 in A/J mice; the affected animals develop lymphocytic myocarditis but with no apparent clinical signs. In this model, the utility of magnetic resonance microscopy (MRM) as a non-invasive modality to determine the cardiac structural and functional changes in animals immunized with Myhc-&#945; 334-352 is shown. EAM and healthy mice were imaged using a 9.4 T (400 MHz) 89 mm vertical core bore scanner equipped with a 4 cm millipede radio-frequency imaging probe and 100 G/cm triple axis gradients. Cardiac images were acquired from anesthetized animals using a gradient-echo-based cine pulse sequence, and the animals were monitored by respiration and pulse oximetry. The analysis revealed an increase in the thickness of the ventricular wall in EAM mice, with a corresponding decrease in the interior diameter of ventricles, when compared with healthy mice. The data suggest that morphological and functional changes in the inflamed hearts can be non-invasively monitored by MRM in live animals. In conclusion, MRM offers an advantage of assessing the progression and regression of myocardial injuries in diseases caused by infectious agents, as well as response to therapies.

This study demonstrates the successful establishment of magnetic resonance microscopy imaging as a non-invasive tool to assess the cardiac abnormalities in mice affected with autoimmune myocarditis. The data indicate that the technique can be used to monitor the disease-progression in live animals.

マウスでの磁気共鳴イメージング顕微鏡による実験的自己免疫性心筋炎における心臓の異常を非侵襲的に評価

Myocarditis is an inflammation of the myocardium, but only ~10% of those affected show clinical manifestations of the disease. To study the immune events ...

Early Detection of Drug-Induced Renal Hemodynamic Dysfunction Using Sonographic Technology in Rats

The kidney normally functions to maintain hemodynamic homeostasis and is a major site of damage caused by drug toxicity. Drug-induced nephrotoxicity is estimated to contribute to 19- 25% of all clinical cases of acute kidney injury (AKI) in critically ill patients. AKI detection has historically relied on metrics such as serum creatinine (sCr) or blood urea nitrogen (BUN) which are demonstrably inadequate in full assessment of nephrotoxicity in the early phase of renal dysfunction. Currently, there is no robust diagnostic method to accurately detect hemodynamic alteration in the early phase of AKI while such alterations might actually precede the rise in serum biomarker levels. Such early detection can help clinicians make an accurate diagnosis and help in in decision making for therapeutic strategy. Rats were treated with Cisplatin to induce AKI. Nephrotoxicity was assessed for six days using high-frequency sonography, sCr measurement and upon histopathology of kidney. Hemodynamic evaluation using 2D and Color-Doppler images were used to serially study nephrotoxicity in rats, using the sonography. Our data showed successful drug-induced kidney injury in adult rats by histological examination. Color-Doppler based sonographic assessment of AKI indicated that resistive-index (RI) and pulsatile-index (PI) were increased in the treatment group; and peak-systolic velocity (mm/s), end-diastolic velocity (mm/s) and velocity-time integral (VTI, mm) were decreased in renal arteries in the same group. Importantly, these hemodynamic changes evaluated by sonography preceded the rise of sCr levels. Sonography-based indices such as RI or PI can thus be useful predictive markers of declining renal function in rodents. From our sonography-based observations in the kidneys of rats that underwent AKI, we showed that these noninvasive hemodynamic measurements may consider as an accurate, sensitive and robust method in detecting early stage kidney dysfunction. This study also underscores the importance of ethical issues associated with animal use in research.

Early stage hemodynamic dysfunction is critical to the development of kidney disease. Yet, detection methodologies are limited. Recent advances in sonography provide a noninvasive, accurate option for early detection of kidney injury. This study outlines a step-by-step, sonographic methodology for detecting kidney dysfunction using a drug-induced nephrotoxicity rat model.

ラットにおける超音波検査技術を用いた薬剤誘発性腎血行動態機能障害の早期発見

The kidney normally functions to maintain hemodynamic homeostasis and is a major site of damage caused by drug toxicity. Drug-induced nephrotoxicity is ...

Cardiac Catheterization in Mice to Measure the Pressure Volume Relationship: Investigating the Bowditch Effect

Animal models that mimic human cardiac disorders have been created to test potential therapeutic strategies. A key component to evaluating these strategies is to examine their effects on heart function. There are several techniques to measure in vivo cardiac mechanics (e.g., echocardiography, pressure/volume relations, etc.). Compared to echocardiography, real-time left ventricular (LV) pressure/volume analysis via catheterization is more precise and insightful in assessing LV function. Additionally, LV pressure/volume analysis provides the ability to instantaneously record changes during manipulations of contractility (e.g., &#946;-adrenergic stimulation) and pathological insults (e.g., ischemia/reperfusion injury). In addition to the maximum (+dP/dt) and minimum (-dP/dt) rate of pressure change in the LV, an accurate assessment of LV function via several load-independent indexes (e.g., end systolic pressure volume relationship and preload recruitable stroke work) can be attained. Heart rate has a significant effect on LV contractility such that an increase in the heart rate is the primary mechanism to increase cardiac output (i.e., Bowditch effect). Thus, when comparing hemodynamics between experimental groups, it is necessary to have similar heart rates. Furthermore, a hallmark of many cardiomyopathy models is a decrease in contractile reserve (i.e., decreased Bowditch effect). Consequently, vital information can be obtained by determining the effects of increasing heart rate on contractility. Our and others data has demonstrated that the neuronal nitric oxide synthase (NOS1) knockout mouse has decreased contractility. Here we describe the procedure of measuring LV pressure/volume with increasing heart rates using the NOS1 knockout mouse model.

This article describes the measurement of murine left ventricular function via pressure/volume analysis at different heart rates.

ボーディッチ影響を調べる：圧力体積関係を測定するために、マウスにおける心臓カテーテル検査

Animal models that mimic human cardiac disorders have been created to test potential therapeutic strategies. A key component to evaluating these ...

Myocardial Infarction in Neonatal Mice, A Model of Cardiac Regeneration

Myocardial infarction induced by coronary artery ligation has been used in many animal models as a tool to study the mechanisms of cardiac repair and regeneration, and to define new targets for therapeutics. For decades, models of complete heart regeneration existed in amphibians and fish, but a mammalian counterpart was not available. The recent discovery of a postnatal window during which mice possess regenerative capabilities has led to the establishment of a mammalian model of cardiac regeneration. A surgical model of mammalian cardiac regeneration in the neonatal mouse is presented herein. Briefly, postnatal day 1 (P1) mice are anesthetized by isoflurane and placed on an ice pad to induce hypothermia. After the chest is opened, and the left anterior descending coronary artery (LAD) is visualized, a suture is placed around the LAD to inflict myocardial ischemia in the left ventricle. The surgical procedure takes 10-15 min. Visualizing the coronary artery is crucial for accurate suture placement and reproducibility. Myocardial infarction and cardiac dysfunction are confirmed by triphenyl-tetrazolium chloride (TTC) staining and echocardiography, respectively. Complete regeneration 21 days post myocardial infarction is verified by histology. This protocol can be used to as a tool to elucidate mechanisms of mammalian cardiac regeneration after myocardial infarction.

This protocol describes a highly reproducible model of cardiac regeneration by surgical induction of myocardial infarction in the left ventricle of postnatal day 1 mice. The method involves induction of hypothermic anesthesia and ligation of the left anterior descending coronary artery.

新生児マウスの心筋梗塞、心臓再生のモデル

Myocardial infarction induced by coronary artery ligation has been used in many animal models as a tool to study the mechanisms of cardiac repair and ...

A Model of Glaucoma Induced by Circumlimbal Suture in Rats and Mice

The circumlimbal suture is a technique for inducing experimental glaucoma in rodents by chronically elevating intraocular pressure (IOP), a well-known risk factor for glaucoma. This protocol demonstrates a step-by-step guide on this technique in Long Evans rats and C57BL/6 mice. Under general anesthesia, a "purse-string" suture is applied on the conjunctiva, around the equator and behind the limbus of the eye. The fellow eye serves as an untreated control. Over the duration of our study, which was a period of 8 weeks for rats and 12 weeks for mice, IOP remained elevated, as measured regularly by rebound tonometry in conscious animals without topical anesthesia. In both species, the sutured eyes showed electroretinogram features consistent with preferential inner retinal dysfunction. Optical coherence tomography showed selective thinning of the retinal nerve fiber layer. Histology of the rat retina in cross-section found reduced cell density in the ganglion cell layer, but no change in other cellular layers. Staining of flat-mounted mouse retinae with a ganglion cell specific marker (RBPMS) confirmed ganglion cell loss. The circumlimbal suture is a simple, minimally invasive and cost-effective way to induce ocular hypertension that leads to ganglion cell injury in both rats and mice.

Chronic ocular hypertension is induced by applying a circumlimbal suture in rats and mice, leading to functional and structural deterioration of the retinal ganglion cells consistent with glaucoma.

ラットおよびマウスの Circumlimbal 縫合による緑内障のモデル

The circumlimbal suture is a technique for inducing experimental glaucoma in rodents by chronically elevating intraocular pressure (IOP), a well-known ...

Isolation of Atrial Myocytes from Adult Mice

The electrophysiological properties of atrial myocytes importantly affect overall cardiac function. Alterations in the underlying ionic currents responsible for the action potential can cause pro-arrhythmic substrates that underlie arrhythmias, such as atrial fibrillation, which are highly prevalent in many conditions and disease states. Isolating adult mouse atrial cardiomyocytes for use in patch-clamp experiments has greatly advanced our knowledge and understanding of the cellular electrophysiology in the healthy atrial myocardium and in the setting of atrial pathophysiology. In addition, studies using genetic mouse models have elucidated the role of a vast array of proteins in regulating atrial electrophysiology. Here we provide a detailed protocol for the isolation of cardiomyocytes from the atrial appendages of adult mice using a combination of enzymatic digestion and mechanical dissociation of these tissues. This approach consistently and reliably yields isolated atrial cardiomyocytes that can then be used to characterize cellular electrophysiology by measuring action potentials and ionic currents in patch-clamp experiments under a number of experimental conditions.

This protocol is used to isolate single atrial cardiomyocytes from the adult mouse heart using a chunk digestion approach. This approach is used to isolate right or left atrial myocytes that can be used to characterize atrial myocyte electrophysiology in patch-clamp studies.

成体マウスからの心房筋細胞の単離

The electrophysiological properties of atrial myocytes importantly affect overall cardiac function. Alterations in the underlying ionic currents ...

Biventricular Assessment of Cardiac Function and Pressure-Volume Loops by Closed-Chest Catheterization in Mice

Assessment of cardiac function is essential to conduct cardiovascular and pulmonary-vascular preclinical research. Pressure-volume loops (PV loops) generated by recording both pressure and volume during cardiac catheterization are vital when assessing both systolic and diastolic cardiac function. Left and right heart function are closely related, reflected in ventricular interdependence. Thus, recording biventricular function in the same animal is important to get a complete assessment of cardiac function. In this protocol, a closed chest approach to cardiac catheterization consistent with the way catheterization is performed in patients is adopted in mice. While challenging, the closed chest strategy is a more physiological approach, because opening the chest results in major changes in preload and afterload that create artifacts, most notably a fall in systemic blood pressure. While high-resolution echocardiography is used to assess rodents, cardiac catheterization is invaluable, particularly when assessing diastolic pressures in both ventricles.
Described here is a procedure to perform invasive, closed chest, sequential left and right ventricular pressure-volume (PV) loops in the same animal. PV loops are acquired using&#160;admittance technology with a mouse pressure-volume catheter and pressure-volume system acquisition. The procedure is described, beginning with the neck dissection, which is required to access the right jugular vein and the right carotid artery, to the insertion and positioning of the catheter, and finally the data acquisition. Then, the criteria required to ensure the acquisition of high-quality PV loops are discussed. Finally, the analysis of the left and right ventricular PV loops and the different hemodynamic parameters available to quantify systolic and diastolic ventricular function are briefly described.

Presented here is a protocol to assess biventricular heart function in mice by generating pressure-volume (PV) loops from the right and left ventricle in the same animal using closed chest catheterization. The focus is on the technical aspect of surgery and data acquisition.

マウスにおける閉鎖胸腔カテーテル法による心機能および圧力容積ループの両心室評価

Assessment of cardiac function is essential to conduct cardiovascular and pulmonary-vascular preclinical research. Pressure-volume loops (PV loops) ...

Cardiac Response to &#946;-Adrenergic Stimulation Determined by Pressure-Volume Loop Analysis

Determination of the cardiac function is a robust endpoint analysis in animal models of cardiovascular diseases in order to characterize effects of specific treatments on the heart. Due to the feasibility of genetic manipulations the mouse has become the most common mammalian animal model to study cardiac function and to search for new potential therapeutic targets. Here we describe a protocol to determine cardiac function&#160;in vivo using pressure-volume loop measurements and analysis during basal conditions and under &#946;-adrenergic stimulation by intravenous infusion of increasing concentrations of isoproterenol. We provide a refined protocol including ventilation support taking into account the positive end-expiratory pressure to ameliorate negative effects during open-chest measurements, and potent analgesia (Buprenorphine) to avoid uncontrollable myocardial stress evoked by pain during the procedure. All together the detailed description of the procedure and discussion about possible pitfalls enables highly standardized and reproducible pressure-volume loop analysis, reducing the exclusion of animals from the experimental cohort by preventing possible methodological bias.

Cardiac Response to &amp;#946;-Adrenergic Stimulation Determined by Pressure-Volume Loop Analysis

Here we describe a cardiac pressure-volume loop analysis under increasing doses of intravenously infused isoproterenol to determine the intrinsic cardiac function and the &#946;-adrenergic reserve in mice. We use a modified open-chest approach for the pressure-volume loop measurements, in which we include ventilation with positive end-expiratory pressure.

圧力量ループ解析によるβ-アドレナリン刺激に対する心臓応答

Determination of the cardiac function is a robust endpoint analysis in animal models of cardiovascular diseases in order to characterize effects of ...

A Large Animal Model for Acute Kidney Injury by Temporary Bilateral Renal Artery Occlusion

Acute kidney injury (AKI) is associated with higher risk for morbidity and mortality post-operatively. Ischemia-reperfusion injury (IRI) is the most common cause of AKI. To mimic this clinical scenario, this study presents a highly reproducible large animal model of renal IRI in swine using temporary percutaneous bilateral balloon-catheter occlusion of the renal arteries. The renal arteries are occluded for 60 min by introducing the balloon-catheters through the femoral and carotid artery and advancing them into the proximal portion of the arteries. Iodinated contrast is injected in the aorta to assess any opacification of the kidney vessels and confirm the success of the artery occlusion. This is furtherly confirmed by the flattening of the pulse waveform at the tip of the balloon catheters. The balloons are deflated and removed after 60 min of bilateral renal artery occlusion, and the animals are allowed to recover for 24 h. At the end of the study, plasma creatinine and blood urea nitrogen significantly increase, while eGFR and urine output significantly decrease. The need for iodinated contrast is minimal and does not affect renal function. Bilateral renal artery occlusion better mimics the clinical scenario of perioperative renal hypoperfusion, and the percutaneous approach minimizes the impact of the inflammatory response and the risk of infection seen with an open approach, such as a laparotomy. The ability to create and reproduce this clinically relevant swine model eases the clinical translation to humans.

This study presents a highly reproducible large animal model of renal ischemia-reperfusion injury in swine using temporary percutaneous bilateral balloon-catheter occlusion of the renal arteries for 60 min and reperfusion for 24 h.

一時的な両側性腎動脈閉塞による急性腎障害の大型動物モデル

Acute kidney injury (AKI) is associated with higher risk for morbidity and mortality post-operatively. Ischemia-reperfusion injury (IRI) is the most ...