我々は、このプロジェクトや施設への親切なアクセスが可能な専門家の助けのために博士コーリーレイノルズとBCMのマウスの表現型のコアを感謝したいと思います。 XHTWは、医学研究でWMケック財団特別若い学者であり、そしてまた、NIH / NHLBIの助成金R01 - HL089598とR01 - HL091947、および筋ジストロフィー協会の助成金＃69238でサポートされています。この作品は、ハートのCaMKIIシグナリングのための財団Leducqアライアンスによって部分的にサポートされています。

1。イメージング研究のための準備マウス<ol><li>前の画像診断に、誘導チャンバ内にマウス（2％イソフルラン0.5 L /分と混合100％O 2）を麻酔。オペレータの安全のために廃ガスをフィルタするようにしてください。誘導室から動物を外し、ネックラインからミッド胸の高さに毛を剃ることをバリカンを使用してください。その後、脱毛クリームと残りの体の毛を取り除く。この製剤は、マウスでは潜在的な望ましくないストレス反応を最小限に抑えるために一日前にイメージング研究に行ってもよい。 </li><li> （ゲルの塗布で角膜の接触を避けるため）強膜の乾燥を防ぐために、両眼にゲルをduralube適用されます。体温を維持するために埋め込まれたECGリードと加熱パッドの上仰臥位で麻酔したマウスを置きます。 </li><li>手続きを通じて定常状態鎮静のレベル（0.5 L /分100％O 2と混合イソフルラン1.0％〜1.5％）を維持するために麻酔のシステムに接続されているノーズコーン内で鼻を置きます。鎮静を確認するために、つま先やテールピンチを実行します。必要に応じて、麻酔のレベルは、450の目標心拍数± 1分間に50ビート（BPM）を得るために調整することができます。 </li><li>ゆっくりと連続的に加熱パッドを介して体内の温度を監視し、調整するために直腸プローブを（潤滑後に）挿入する。それは温度と心拍数でさえ緩やかな変化がマウスの心機能に影響を与えるとして、（37.0℃± 0.5℃）の狭い範囲内で体温を維持することが重要です。 </li><li>フォーパウとテープそれらのECG電極に、電極のゲルを適用します。 </li></ol> 2。心臓の収縮機能の評価<ol><li>この手順を開始するには、心臓を覆う面積主に、胸に予熱した超音波ゲルの層を適用する。ゲルは、おおよその体温まで温めてください。冷たいゲルの体積が急速に体温の損失の割合を追加してもかまいません。超音波画像と干渉する可能性ゲル中の気泡を、避けてください。 </li><li>わずかな角度で軽く上向きの位置（ヘッドアップ）でマウスを固定化する。マイクロマニピュレータを用いて、プローブと心臓の間に90 °の角度で超音波プローブを固定化する。 </li><li>短軸心エコー測定を行う開始するには、parasternally胸部の上にプローブを下げます。これは信号を歪ませるので、直接に胸骨の上または皮膚にプローブを置かないでください。 </li><li>最初に、我々は傍胸骨短軸に沿ってビューを取得するために、2次元（2D）画像を（&#39;B -モード&#39;）が実行されます。動物の心臓の大きさに応じて完全な画像を得るために、プローブの表示領域を調整します。 </li><li>この方向で適切な画像は、左心室と右心室壁のわずかな部分が含まれます。矢印は（ビデオ参照）前外側および後内側乳頭筋、LVの後部と前部壁、脳室内隔壁、および右心室壁のわずかな部分を示している。これらの測定時には、潜在的な壁運動異常（例えば、運動低下、akinasia、非同期）または動脈瘤に特に注意してください。 </li><li>次に、我々は、心臓の大きさと収縮性の微細な測定値を得るために、1次元（1D）のビューを提供するM -モード心エコー図を、使用します。ストアは、収縮期左心室機能のパラメータの後の評価のための画像を取得しました。 </li></ol> 3。心臓の拡張機能を評価する<ol><li>それでも傍胸骨短軸を表示している間、我々は心筋運動の速度を測定するための組織ドップラーイメージング（TDI）を実行することができます。関心領域は、半径方向の軸の評価のための後方左心室壁を含むようにマークされます。 IVRT、E&#39;、&#39;、およびIVCT：得られる波形は、拡張機能を評価するための4つのピークを持つことになります。 S&#39;は、収縮期速度を表します。 （図3B）これらのパラメータは、代表的な結果のセクションで後述する。 </li><li>パルス波ドップラー（PWD）は、心筋組織内の特定の深さで、小さなエリア内の血流速度を測定するために使用することができます。画像トランス僧帽弁フローパターンをするために、トレンデレンブルグポジションで後方に動物を傾けます。 、上向きプローブは心尖と直交になるようにプローブを傾けます。 </li><li>今僧帽弁の動きを遅くする300〜350 BPM、に心拍数を下げるためにイソフルランレベルを増加させる。比較研究のために、動物の間で同様の心拍数を維持することが重要です。 </li><li>バルブ前後の流れを測定する基準点として僧帽弁の動きを視覚化する。僧帽弁の先端にサンプル量を置きます。 </li><li> PWDを使用して僧帽弁全体の流れのパターンを測定します。二つの波が特徴的に見られ、心室の受動的な充填（初期の[E]波）を表し、もう一つは心房収縮期（心房[A]波）を持つアクティブな充填と一致して一つ。健康な心臓では、E -波の速度は、波（図3C）のそれよりわずかに大きいです。 </li><li>すべての測定が完了すると、電極のゲル（軽く標準ガーゼパッドで拭いて）と、動物から制約を削除します。気ままな動物は、直立した状態で加熱されたECGパッドの上に回復して、麻酔をオフにすることができます。マウスが覚醒したとき、そのケージに戻します。 </li></ol> 4。代表的な経胸壁心エコーの結果非侵襲的心エコー研究は心臓疾患のマウスモデルでは左室の形態と機能を評価するために使用することができます。4,5この手法は広く使われていると左室機能を評価するため、端末の手順に代わるものを提供され、そのような心臓内の圧容積ループmeasurements.8としてまたはex vivoでの作業心臓モデルが。経胸壁M -モード心エコー図によるLV室の大きさの9評価は、異常LV室の肥大や心臓病の様々なモデルの増加壁の厚さを検出することができます。パルス波ドップラーと組み合わせてこのように5、経胸壁心エコー検査は、 、収縮期およびマウスの拡張期心機能の非侵襲的評価のための包括的な手段を構成している。 <img src="/files/ftp_upload/1738/1738fig1.jpg" alt="図1" /> 図1。心エコー検査とドップラーイメージングのin vivoマイクロイメージングシステムでVEVO 770高解像度の概要は、（A）私たちは、生理学的モニタリングユニット、EKGボード、およびRMV 30MHzのスキャンヘッドとVisualSonics統合された鉄道システムを使用してください。 （B）マウスが配置され、適切に統合されたECG電極（ゴールドカラー）と加熱基板上に拘束される。四肢は、ECG電極にテープで固定されています。 （CD）パルス波ドップラーのために適切な角度を示す写真は、プロトコルのセクション4で説明されている拡張機能の測定値を、取得するために使用。収縮機能の測定用プローブの向きは、ビデオのプロトコルでのショーです。 <img src="/files/ftp_upload/1738/1738fig2.jpg" alt="図2" /> 図2。代表的な2次元の心エコー画像（Bモード）。左室前（AW）と後部（PW）の壁、心室内の隔壁（SW）、及び側壁（LW）を示す（A）パラ胸骨短軸像。左心室内腔の直径は、左心室内径（LVID）として測定することができる。アスタリスクは、後内側乳頭筋を示している。 E /ピーク速度を測定するための僧帽弁以上の表示領域を持つ（B）アピカル四腔像。 MVAL、僧帽弁前尖、MVPL、僧帽弁後尖、RV、右心室、左心室は、心室を残した。 <img src="/files/ftp_upload/1738/1738fig3.jpg" alt="図3" /> 図3。心エコー検査とドップラーデータの収集と定量化は、この図は、図2に示した断層心エコー法の画像に対応する取得したデータの代表的な画像が含まれています。 （A）Mモードでは、収縮末期（ESD）と拡張末期径（EDD）を示す線をトレース。 LVAWD / Sは、心室前壁の厚さ（拡張期/収縮期）を残し、LVPWD / S、左室後壁の厚さ（拡張期/収縮期）。 （B）LV後壁の組織ドップラーイメージングのための代表的なトレーシング。 IVRT、等容性弛緩時間、IVCT、等容収縮時間。 E&#39;波がLVの拡張早期充満時の僧帽弁輪の動きに対応しており、&quot;波がLVの充填年代後半に心房収縮に由来する。 S&#39;は、収縮期速度を表しています。 （C）僧帽弁尖の先端のパルス波ドップラー記録は拡張早期速度（E）、拡張期収縮による後期拡張期血流速度（）、およびE / A比を引き出すことができるから僧帽弁流入速度パターンが用意されています。 IVRTはまた、拡張機能と充填圧力を特徴付けるために有用な変数です。 ETは駆出時間を示します。

<ol>
	<li>Zhang, T. M. a. i. e. r., S, L., Dalton, N. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+deltaC+isoform+of+CaMKII+is+activated+in+cardiac+hypertrophy+and+induces+dilated+cardiomyopathy+and+heart+failure.">The deltaC isoform of CaMKII is activated in cardiac hypertrophy and induces dilated cardiomyopathy and heart failure.</a> Circ Res. 92 (8), 912-912 (2003).</li><li>Srivastava, D., Thomas, T., Lin, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+cardiac+mesodermal+and+neural+crest+development+by+the+bHLH+transcription+factor,+dHAND.">Regulation of cardiac mesodermal and neural crest development by the bHLH transcription factor, dHAND.</a> Nat Genet. 16 (2), 154-154 (1997).</li><li>Sood, S., Chelu, M. G., van Oort, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracellular+calcium+leak+due+to+FKBP12.6+deficiency+in+mice+facilitates+the+inducibility+of+atrial+fibrillation.">Intracellular calcium leak due to FKBP12.6 deficiency in mice facilitates the inducibility of atrial fibrillation.</a> Heart Rhythm. 5 (7), 1047-1047 (2008).</li><li>Gardin, J. M., Siri, F. M., Kitsis, R. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Echocardiographic+assessment+of+left+ventricular+mass+and+systolic+function+in+mice.">Echocardiographic assessment of left ventricular mass and systolic function in mice.</a> Circ Res. 76 (5), 907-907 (1995).</li><li>Tanaka, N., Dalton, N., Mao, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transthoracic+echocardiography+in+models+of+cardiac+disease+in+the+mouse.">Transthoracic echocardiography in models of cardiac disease in the mouse.</a> Circulation. 94 (5), 1109-1109 (1996).</li><li>Patten, R. D., Aronovitz, M. J., Bridgman, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+pulse+wave+and+color+flow+Doppler+echocardiography+in+mouse+models+of+human+disease.">Use of pulse wave and color flow Doppler echocardiography in mouse models of human disease.</a> J Am Soc Echocardiogr. 15 (7), 708-708 (2002).</li><li>Garcia-Fernandez, M. A., Azevedo, J., Moreno, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regional+Left+Ventricular+Diastolic+Dysfunction+Evaluated+by+Pulsed-Tissue+Doppler+Echocardiography.">Regional Left Ventricular Diastolic Dysfunction Evaluated by Pulsed-Tissue Doppler Echocardiography.</a> Echocardiography. 16 (5), 491-491 (1999).</li><li>Pacher, P., Nagayama, T., Mukhopadhyay, P. <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+cardiac+function+using+pressure-volume+conductance+catheter+technique+in+mice+and+rats.">Measurement of cardiac function using pressure-volume conductance catheter technique in mice and rats.</a> Nat Protoc. 3 (9), 1422-1422 (2008).</li><li>Larsen, T. S., Belke, D. D., Sas, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Pflugers Arch. 437 (6), 979-979 (1999).</li><li>Roth, D. M., Swaney, J. S., Dalton, N. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+anesthesia+on+cardiac+function+during+echocardiography+in+mice.">Impact of anesthesia on cardiac function during echocardiography in mice.</a> Am J Physiol Heart Circ Physiol. 282 (6), H2134-H2134 (2002).</li></ol>

M -モード心エコー図を使用するときにマウスの異なるグループまたは遺伝子型間の比較を容易にするためにマウスのコホート内麻酔のレベルは、10体の温度、および心拍数を標準化することが重要です。拡張機能のPWDの評価のために、心拍数はマウス心臓の拡張期特性を評価するために小さくする必要があります。動物の生体機能は密接に血行動態の障害や死を防ぐために観察する必要があります。一方、M -モデルの心エコー検査を用いて収縮機能の測定のために、毎分400拍以下の心拍数は、拡張末期径が増加LVの充填のために増加する可能性があります。

*必要なソフトウェアは、B -モードのアプリケーション、パルス波ドップラーアプリケーション、および心血管解析ツールのパッケージを含むVEVOのソフトウェアです。

transthoracic echocardiography in mice

近年では、マウスモデルは遺伝子発現の変化に起因する心機能障害の分子機構を研究するための主要手段となっている。トランスジェニック、遺伝子ターゲッティング方法は、変更された心臓の大きさと機能を持つマウスを作製するために使用することができます。<sup&gt; 1月3日</sup&gt;そしてその結果として、<em&gt; in vivoで</em&gt;技術は、彼らの心臓の表現型を評価する研究が必要である。経胸壁心エコー検査、脈波ドップラー（PWD）、および組織ドップラーイメージング（TDI）は、マウスの心臓の寸法測定を提供し、心臓の収縮期および拡張期の性能の程度を定量化するために使用することができます。 Mモードエコーは心臓の大きさと収縮性の定量化に使用されるのに対し、二次元画像化は、異常な解剖学や左心室の動きを検出するために使用されます。<sup&gt; 4,5</sup&gt;さらに、PWDは、乱流のローカライズされた速度を定量化するために使用されています<sup&gt; 6</sup&gt;一方、TDIは心筋運動の速度を測定するために使用されます。<sup&gt; 7</sup&gt;このように、経胸壁心エコー検査は、マウスの心機能の非侵襲的評価のための包括的な方法を提供しています。

Watch this Scientific Journal Video about Transthoracic Echocardiography in Mice at JoVE.com

Transthoracic Echocardiography in Mice

経胸壁心エコー検査は、マウスの心機能の評価のための非侵襲的方法を提供しています。超音波検査とドップラーイメージングモダリティの組み合わせは、一緒に心臓の収縮期および拡張期のパフォーマンスの評価を提供する、心臓と心臓内の血流の寸法測定を、得るために使用することができます。

マウスにおける経胸壁心エコー

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene ...

Research

JoVE Journal

Medicine

61.5K ビュー.  Baylor College of Medicine (BCM). 経胸壁心エコー検査は、マウスの心機能の評価のための非侵襲的方法を提供しています。超音波検査とドップラーイメージングモダリティの組み合わせは、一緒に心臓の収縮期および拡張期のパフォーマンスの評価を提供する、心臓と心臓内の血流の寸法測定を、得るために使用することができます。

ビデオ: Transthoracic Echocardiography in Mice

Murine Echocardiography and Ultrasound Imaging

Rodent models of cardiac pathophysiology represent a valuable research tool to investigate mechanism of disease as well as test new therapeutics.1 Echocardiography provides a powerful, non-invasive tool to serially assess cardiac morphometry and function in a living animal.2 However, using this technique on mice poses unique challenges owing to the small size and rapid heart rate of these animals.3 Until recently, few ultrasound systems were capable of performing quality echocardiography on mice, and those generally lacked the image resolution and frame rate necessary to obtain truly quantitative measurements. Newly released systems such as the VisualSonics Vevo2100 provide new tools for researchers to carefully and non-invasively investigate cardiac function in mice. This system generates high resolution images and provides analysis capabilities similar to those used with human patients. Although color Doppler has been available for over 30 years in humans, this valuable technology has only recently been possible in rodent ultrasound.4,5 Color Doppler has broad applications for echocardiography, including the ability to quickly assess flow directionality in vessels and through valves, and to rapidly identify valve regurgitation. Strain analysis is a critical advance that is utilized to quantitatively measure regional myocardial function.6 This technique has the potential to detect changes in pathology, or resolution of pathology, earlier than conventional techniques. Coupled with the addition of three-dimensional image reconstruction, volumetric assessment of whole-organs is possible, including visualization and assessment of cardiac and vascular structures. Murine-compatible contrast imaging can also allow for volumetric measurements and tissue perfusion assessment.

This video demonstrates use of a rail-mounted high-frequency ultrasound probe to perform echocardiography on an anesthetized mouse. The methods describe both conventional two-dimensional and M-mode measurements of cardiac function in addition to newer, more powerful tools such as color Doppler, strain analysis, as well as general and targeted contrast imaging.

マウス心エコー検査と超音波イメージング

Rodent models of cardiac pathophysiology represent a valuable research tool to investigate mechanism of disease as well as test new therapeutics.1  ...

医学

Murine Fetal Echocardiography

Transgenic mice displaying abnormalities in cardiac development and function represent a powerful tool for the understanding the molecular mechanisms underlying both normal cardiovascular function and the pathophysiological basis of human cardiovascular disease. Fetal and perinatal death is a common feature when studying genetic alterations affecting cardiac development 1-3. In order to study the role of genetic or pharmacologic alterations in the early development of cardiac function, ultrasound imaging of the live fetus has become an important tool for early recognition of abnormalities and longitudinal follow-up. Noninvasive ultrasound imaging is an ideal method for detecting and studying congenital malformations and the impact on cardiac function prior to death 4. It allows early recognition of abnormalities in the living fetus and the progression of disease can be followed in utero with longitudinal studies 5,6. Until recently, imaging of fetal mouse hearts frequently involved invasive methods. The fetus had to be sacrificed to perform magnetic resonance microscopy and electron microscopy or surgically delivered for transillumination microscopy. An application of high-frequency probes with conventional 2-D and pulsed-wave Doppler imaging has been shown to provide measurements of cardiac contraction and heart rates during embryonic development with databases of normal developmental changes now available 6-10. M-mode imaging further provides important functional data, although, the proper imaging planes are often difficult to obtain. High-frequency ultrasound imaging of the fetus has improved 2-D resolution and can provide excellent information on the early development of cardiac structures 11.

Fetal and perinatal death is a common feature when studying genetic alterations affecting cardiac development. High-frequency ultrasound imaging has improved 2-D resolution and can provide excellent information on early cardiac development and is an ideal method to detect the impact on cardiac structure and function prior to death.

ネズミの胎児心エコー検査

Transgenic mice displaying abnormalities in  cardiac development and function represent a powerful tool for the understanding  the molecular mechanisms ...

In utero Measurement of Heart Rate in Mouse by Noninvasive M-mode Echocardiography

Congenital heart disease (CHD) is the most frequent noninfectious cause of death at birth. The incidence of CHD ranges from 4 to 50/1,000 births (Disease and injury regional estimates, World Health Organization, 2004). Surgeries that often compromise the quality of life are required to correct heart defects, reminding us of the importance of finding the causes of CHD. Mutant mouse models and live imaging technology have become essential tools to study the etiology of this disease. Although advanced methods allow live imaging of abnormal hearts in embryos, the physiological and hemodynamic states of the latter are often compromised due to surgical and/or lengthy procedures. Noninvasive ultrasound imaging, however, can be used without surgically exposing the embryos, thereby maintaining their physiology. Herein, we use simple M-mode ultrasound to assess heart rates of embryos at E18.5 in utero. The detection of abnormal heart rates is indeed a good indicator of dysfunction of the heart and thus constitutes a first step in the identification of developmental defects that may lead to heart failure.

In utero Measurement of Heart Rate in Mouse by Noninvasive M-mode Echocardiography

Ultra-high frequency ultrasound is a powerful live imaging tool to examine cardiac abnormalities in small animals. Its noninvasiveness allows maintaining the physiologic state of embryos. Herein, we show the use of M-mode ultrasound to measure the heart rates of embryos at E18.5 in utero.

非侵襲Mモード心エコー検査によるマウスでの心拍数の子宮内測定で

Congenital heart disease (CHD) is the most frequent noninfectious cause of death at birth. The incidence of CHD ranges from 4 to 50/1,000 births (Disease ...

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, ...

Ultrasound-guided Transthoracic Intramyocardial Injection in Mice

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. Experiments involving myocardial injection are currently performed by direct surgical access through a thoracotomy. While convenient when performed at the time of another experimental manipulation such as coronary artery ligation, the need for an invasive procedure for intramyocardial delivery limits potential experimental designs. With ever improving ultrasound resolution and advanced noninvasive imaging modalities, it is now feasible to routinely perform ultrasound-guided, percutaneous intramyocardial injection. This modality efficiently and reliably delivers agents to a targeted region of myocardium. Advantages of this technique include the avoidance of surgical morbidity, the facility to target regions of myocardium selectively under ultrasound guidance, and the opportunity to deliver injectate to the myocardium at multiple, predetermined time intervals. With practiced technique, complications from intramyocardial injection are rare, and mice quickly return to normal activity on recovery from anesthetic. Following the steps outlined in this protocol, the operator with basic echocardiography experience can quickly become competent in this versatile, minimally invasive technique.

Echocardiography-guided percutaneous intramyocardial injection represents an efficient, reliable, and targetable modality for the delivery of gene transfer agents or cells into the murine heart. Following the steps outlined in this protocol, the operator can quickly become competent in this versatile, minimally invasive technique.

マウスにおける超音波ガイド下経胸壁心筋内注射

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. ...

Carotid Artery Infusions for Pharmacokinetic and Pharmacodynamic Analysis of Taxanes in Mice

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study model. As the use of mouse models are often a vital step in preclinical drug discovery and drug development1-8, it is necessary to design a system to introduce drugs into mice in a uniform, reproducible manner. Ideally, the system should permit the collection of blood samples at regular intervals over a set time course. The ability to measure drug concentrations by mass-spectrometry, has allowed investigators to follow the changes in plasma drug levels over time in individual mice1, 9, 10. In this study, paclitaxel was introduced into transgenic mice as a continuous arterial infusion over three hours, while blood samples were simultaneously taken by retro-orbital bleeds at set time points. Carotid artery infusions are a potential alternative to jugular vein infusions, when factors such as mammary tumors or other obstructions make jugular infusions impractical. Using this technique, paclitaxel concentrations in plasma and tissue achieved similar levels as compared to jugular infusion. In this tutorial, we will demonstrate how to successfully catheterize the carotid artery by preparing an optimized catheter for the individual mouse model, then show how to insert and secure the catheter into the mouse carotid artery, thread the end of the catheter out through the back of the mouse&#8217;s neck, and hook the mouse to a pump to deliver a controlled rate of drug influx. Multiple low volume retro-orbital bleeds allow for analysis of plasma drug concentrations over time.

This method was developed with the goal of delivering a steady drug solution via the carotid artery, to assess the pharmacokinetics of novel drugs in mouse models.

マウスにおけるタキサンの薬物動態学的および薬力学的分析のための頸動脈煎茶

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study ...

Transthoracic Speckle Tracking Echocardiography for the Quantitative Assessment of Left Ventricular Myocardial Deformation

The value of conventional echocardiography is limited by differences in inter-individual image interpretation and therefore largely dependent on the examiners&#39; expertise. Speckle tracking Echocardiography (STE) is a promising but technically challenging method that can be used to quantitatively assess regional and global systolic and diastolic myocardial performance. Myocardial strain and strain rate can be measured in all three dimensions&#160;&#8212; radial, circumferential, longitudinal &#8212; of myocardial deformation. Standard cross-sectional two-dimensional B-mode images are recorded and subsequently postprocessed by automated continuous frame-by-frame tracking and motion analysis of speckles within the myocardium. Images are recorded as digital loops and synchronized to a 3-lead EKG for timing purposes. Longitudinal deformation is assessed in the apical 4-, 3-, and 2-chamber views. Circumferential and radial deformation are measured in the parasternal short axis plane.
Optimal image quality and accurate tissue tracking are paramount for the correct determination of myocardial performance parameters. Utilizing transthoracic STE in a healthy volunteer, the present article is a detailed outline of the essential steps and potential pitfalls of quantitative echocardiographic myocardial deformation analysis.

Speckle tracking echocardiography is an emerging diagnostic imaging technique for the quantitative assessment of global and regional myocardial performance. Standard view echocardiographic motion images are recorded and deformation parameters are subsequently measured by automated continuous frame-by-frame tracking and motion analysis of speckles within the B-mode images of the myocardium.

左心室心筋変形の定量的評価のための経胸壁スペックル追跡心エコー検査

The value of conventional echocardiography is limited by differences in inter-individual image interpretation and therefore largely dependent on the ...

Murine Echocardiography of Left Atrium, Aorta, and Pulmonary Artery

The present methodology teaches the investigator how to measure and use the LAV as a surrogate of chronic elevations in Left Ventricular diastolic pressure through echocardiography, as well as to obtain measurements of the Aorta and PA diameter in mice.
Mice older than 10 d of age can be analyzed using the present technique. The technique is composed of 3 main steps: set-up, image acquisition, and image analysis. The set-up step consists of getting the mouse anesthetized with 1% isoflurane, shaving it, and taping it in a supine position to a heated EKG board where the image acquisition will take place. The image acquisition step consists of learning to identify the cardiac structures and obtaining all the required images with its correspondent probe and axis in order to be able to calculate volumes and diameters. The image analysis step consists of measuring the previously acquired images with the aid of computer software.
Advantages of the proposed technique include a fast (15 min) procedure that would allow the researcher to evaluate interventions in a non-invasive, non-terminal approach and therefore follow the same mouse over time; each mouse can be used as its own control. This fact plus having the same operator perform all the acquisition and analysis for the entire experiment minimizes the limitation of operator-dependency. The present methodology is useful for mouse researchers in cardiovascular and pulmonary medicine.

The following protocol describes the methodology for the acquisition and analysis of echocardiographic images used to obtain the Left Atrial Volume (LAV), Aorta (Ao) diameter, and Pulmonary Artery (PA) diameter in mice. This technique is a non-invasive, non-terminal procedure that allows assessment of the cardiopulmonary function.

左心房、大動脈、肺動脈のマウス心エコー

The present methodology teaches the investigator how to measure and use the LAV as a surrogate of chronic elevations in Left Ventricular diastolic ...

2D and 3D Echocardiography in the Axolotl (Ambystoma Mexicanum)

Cardiac malfunction as a result of ischemic heart disease is a major challenge, and regenerative therapies to the heart are in high demand. A few model species such as zebrafish and salamanders that are capable of intrinsic heart regeneration hold promise for future regenerative therapies for human patients. To evaluate the outcome of cardioregenerative experiments it is imperative that heart function can be monitored. The axolotl salamander (A. mexicanum) represents a well-established model species in regenerative biology attaining sizes that allows for evaluation of cardiac function. The purpose of this protocol is to establish methods to reproducibly measure cardiac function in the axolotl using echocardiography. The application of different anesthetics (benzocaine, MS-222, and propofol) is demonstrated, and the acquisition of two-dimensional (2D) echocardiographic data in both anesthetized and unanesthetized axolotls is described. 2D echocardiography of the three-dimensional (3D) heart can suffer from imprecision and subjectivity of measurements, and to alleviate this phenomenon a solid method, namely intra/inter-operator/observer analysis, to measure and minimize this bias is demonstrated. Finally, a method to acquire 3D echocardiographic data of the beating axolotl heart at a very high spatiotemporal resolution and with pronounced blood-to-tissue contrast is described. Overall, this protocol should provide the necessary methods to evaluate cardiac function and model anatomy, and flow dynamics in the axolotl using ultrasound imaging with applications in both regenerative biology and general physiological experiments.

2D and 3D Echocardiography in the Axolotl Ambystoma Mexicanum

Here we present echocardiography protocols for two-dimensional and three-dimensional image acquisition of the beating heart of the axolotl salamander (Ambystoma mexicanum), a model species in heart regeneration. These methods allow for longitudinal evaluation of cardiac function at a high spatiotemporal resolution.

ウーパールーパー (アホロートル メキシコマンネングサ) で 2 D および 3 D 心エコー検査

Cardiac malfunction as a result of ischemic heart disease is a major challenge, and regenerative therapies to the heart are in high demand. A few model ...

Electromagnetic Navigation Transthoracic Nodule Localization for Minimally Invasive Thoracic Surgery

The increased use of chest computed tomography (CT) has led to an increased detection of pulmonary nodules requiring diagnostic evaluation and/or excision. Many of these nodules are identified and excised via minimally invasive thoracic surgery; however, subcentimeter and subsolid nodules are frequently difficult to identify intra-operatively. This can be mitigated by the use of electromagnetic transthoracic needle localization. This protocol delineates the step-by-step process of electromagnetic localization from the pre-operative period to the postoperative period and is an adaptation of the electromagnetically guided percutaneous biopsy previously described by Arias et al. Pre-operative steps include obtaining a same day CT followed by the generation of a three-dimensional virtual map of the lung. From this map, the target lesion(s) and an entry site are chosen. In the operating room, the virtual reconstruction of the lung is then calibrated with the patient and the electromagnetic navigation platform. The patient is then sedated, intubated, and placed in the lateral decubitus position. Using a sterile technique and visualization from multiple views, the needle is inserted into the chest wall at the prechosen skin entry site and driven down to the target lesion. Dye is then injected into the lesion and, then, continuously during needle withdrawal, creating a tract for visualization intra-operatively. This method has many potential benefits when compared to the CT-guided localization, including a decreased radiation exposure and decreased time between the dye injection and the surgery. Dye diffusion from the pathway occurs over time, thereby limiting intra-operative nodule identification. By decreasing the time to surgery, there is a decrease in wait time for the patient, and less time for dye diffusion to occur, resulting in an improvement in nodule localization. When compared to electromagnetic bronchoscopy, airway architecture is no longer a limitation as the target nodule is accessed via a transparenchymal approach. Details of this procedure are described in a step-by-step fashion.

Presented here is a protocol for lung nodule localization using dye marking via electromagnetically navigated transthoracic needle access. The technique described here can be accomplished in the peri-operative period to optimize nodule localization and to successful resection when performing minimally invasive thoracic surgery.