Name: intrauterine telemetry to measure mouse contractile pressure in vivo
Uploaded: 2015-04-06T15:00:00.000+00:00
Duration: 7 min 3 s
Description: Watch this Scientific Journal Video about Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo at JoVE.com

This work was supported by funding from the March of Dimes FY12-133 (S.K.E.) and the National Institutes of Health R01HD037831 (S.K.E.). We would like to thank Dr. Deborah Frank for critical review of the manuscript.

注：国立衛生研究所が定める動物の管理と使用のためのガイドラインを遵守し、すべての動物の手順。すべてのプロトコルは、セントルイスのワシントン大学の動物実験委員会によって承認された。 注：このプロトコルの具体的な材料や設備材料および装置テーブルを一覧表示されます。 雌マウスの1時限繁殖<ol><li>男性との2時間の時間ウィンドウで生後2と6ヶ月の間に成人女性を繁殖。具体的な繁殖時間限り、実験の全体​​のための一貫性が保たれているように必要とされていません。 </li><li>交尾栓の存在によって妊娠を確認してください。プラグは初日後性交0（dpc0）と見られた日と時間を指定します。圧力記録を開始する際に特定の時間を覚えています。 </li><li> dpc8-13に手術を行います。正確なDPCはマウス系統に依存します。 </li><li>マウスは、手術の前にPE妊娠しているかどうかを判断するには麻酔を投与する前に、撮像システムに結合された40 MHzのリニアアレイプローブ腹部のrform音波イメージング。これは妊娠嚢の可視化を可能にします。超音波システムが利用できない場合、マウスの体重を使用する。 注：dpc0とdpc8と腹部の膨満の間に少なくとも2グラムの体重増加は妊娠の良い指標である。 </li></ol> 2.テレメトリ手術準備<ol><li>手術前24時間以内の楽器、ガーゼ、綿棒、外科用ドレープ、及びピペットチップを滅菌するオートクレーブを使用してください。 </li><li> 70％エタノールで清掃手術表面。 </li><li> （げっ歯類に特化した）加熱パッドとビーズ滅菌器の電源をオンにします。 </li></ol> 3.テレメトリ手術<ol><li>麻酔は、1~2リットル/分の酸素流量で4~5％のイソフルランを使用。 </li><li>マウスは麻酔の兆候を示すまで待ってから、ブプレノルフィンを皮下注射する（鎮痛剤：20グラム当たり0.1ミリリットル）。 </li><li>膀胱へのダウンリブの底からマウスの腹部を剃る。 </li><li>予め温め加熱パッド上で手術テーブルにマウスを持参し、乾燥を防ぐために眼軟膏をマウスの目をカバーしています。 </li><li>無菌テクニックを開始します。滅菌手袋を着用し、ヨウ素とエタノールスクラブを配置している無菌面としてラッパーを保つ。 </li><li>パッケージまたは生理食塩水からテレメータを取り外し、滅菌ガーゼの上に配置するために滅菌ピンセットを使用しています。 <ol><li>ゲルとカテーテル先端を埋めるために（テレメータサプライヤーによって提供される）注射器を使用してください。穏やかにカテーテル内にゲルを描画するのに十分な負圧を生成するカテーテルを絞る。 </li></ol></li><li>ピペットで無菌のチップを置きます。ピペット2外科接着剤のμL及び滅菌表面にピペットを設定する。 </li><li>ヨウ素とした後、70％エタノールでエリアを綿棒、手術部位を清掃する。 </li><li>十分な大きさの手術ドレープの穴をカットマウスオーバー切開と場所のために必要な面積のために。 </li><li>マウスが完全に切開を行う前に麻酔をかけていることを確認するために足ピンチ（ペダル応答）を実行します。 </li><li>小さな垂直正中切開を行います。次に、基本的な体壁筋を通して類似の切開を作る。 </li><li>優しく体腔から子宮を引き出し、生存可能であり、ほとんどの子犬を含む子宮角を見つけます。 <ol><li>オプション - miRNAの追加については、テレメータの挿入前に子宮の筋肉層にウイルスベクターを注入する。 </li></ol></li><li>エッジスプリングはさみをカットする3ミリメートルと子宮角の先端に小さな切開を行います。 </li><li>子宮壁と胎児の嚢の間、圧迫することなく、カテーテルを通します。その脱落を減らすために、いくつかの袋を過ぎてカテーテルを挿入します。胎児の嚢は、挿入によって妨害されていないことを確認してください。 </li><li> Uにカテーテルを接着するテレメータ挿入部位に外科的接着剤をピペットterineホーンと子宮角の外にスライドするからカテーテルを防ぐ。剛性になるために接着剤のために数秒待ってから、慎重に体腔内子宮をバックに配置します。 </li><li>カテーテル挿入部位の反対側に体腔内テレメータを置く。 </li><li> 6.0吸収性縫合糸で閉じ体腔を縫合。まず、財布ステッチ、その後三から四個々のステッチを行う。 </li><li>同じ技術を使用して皮膚を縫合するが、6-0非吸収性縫合糸。 </li><li>スワブジブカイン（局所鎮痛剤）切開部位上に軟膏。 </li><li>動物を再水和を助けるために滅菌生理食塩水を皮下の0.3〜0.4ミリリットルを注入。 </li><li>それは完全に目を覚ましになるまで、手術後の動物を監視します。それは重く、麻酔したマウスを窒息することができ、自由に寝具、特定のタイプのように、テーブルの上にその頭を保持できるようになるまで戻って、そのケージにマウスを置かないでください。 30〜45分間麻酔をかけてきたマウスの場合、人は目を期待するべきであるEマウスは1時間と15分までに完全に目を覚ましすべき。 </li><li>追加の手術を行う場合は、70％エタノールとビーズで楽器を拭く再使用する前に滅菌する。 </li></ol> 4.手術後の回復<ol><li>ログ内の毎日の手術後の進行状況を監視します。体重増加や損失をカタログや無気力、出血、または外科的切開の不完全な閉鎖を監視。 <ol><li>マウス軟化しマウス飼料（〜アップルソースの一貫性）や特殊な回復ダイエット食品フィード。 </li><li>縫合糸を調べ、それらが引き出されていないことを確認しますが、過度にマウスを処理しないようにしてください。 </li></ol></li></ol> 5.テレメトリレコーディング<ol><li> （マウスが手術から回復した少なくとも2〜3日後）に興味のある日には、テレメーターをオンにするには、マウスの近くに磁石を配置します。レシーバをマウスケージを置きます。テレメーターが有効化されている場合、受信機上のライトがオンにする必要があります。 </li><li>真新しいtelemeのキャリブレーション<html>提供メーカー固有のキャリブレーションとTERS。再利用テレメータキャリブレーション仕様は、ソフトウェアに保持されます。 </li><li>ソフトウェアの中では、「動物」を右クリックして録音を開始し、最大500 Hzのレートでサンプリングを可能にする「連続サンプリングを開始、「クリックしてください。ソフトウェアは保存し、トレースするように設定されていることを確認します。 注：サンプリングマウスのアイコンが緑色に変わったら、圧力が記録されている。配達中にマウスを乱すことは中断したり、労働を変えるので、慎重に観察することができます。 </li><li>興味の配達や時間経過後、「動物」を右クリックして記録し、「すべて、録音を停止する」を選択することを停止する。テレメータ電池は一般的に唯一の連続記録の1.5カ月続くように、バッテリ寿命を節約するためにテレメータをオフにマグネットを使用してください。 </li><li> CO 2過剰投与によりマウスを安楽死させるとテレメータを回復。子犬は、断頭により安楽死させる。 </li></ol>TLE &quot;&gt; 6。テレメータ滅菌<ol><li>室温で脱イオン水に一晩で1％の酵素洗剤の溶液中にテレメータを置きます。 </li><li>脱イオン水でテレメータをすすぎ、カテーテルを圧迫しないように注意して、すべての組織と接着剤を取り除く。 </li><li>滅菌するために、室温で24時間、2％グルタルアルデヒドでテレメータをインキュベートする。 </li><li>滅菌生理食塩水とのテレメータをすすぎ、次の注入まで滅菌生理食塩水に保管したり改装するために戻っメーカーに送信される。組織は滅菌後のカテーテルの内側に配置されている場合テレメータを改装する必要があります。典型的には、テレメータを改装する必要が前に4~5回使用することができる。 </li></ol>

<ol>
	<li>Slattery, M. M., Morrison, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preterm+delivery.">Preterm delivery.</a> Lancet. 360, 1489-1497 (2002).</li><li>Goldenberg, R. L., Culhane, J. F., Iams, J. D., Romero, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidemiology+and+causes+of+preterm+birth.">Epidemiology and causes of preterm birth.</a> Lancet. 371, 75-84 (2008).</li><li>Keelan, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pharmacological+inhibition+of+inflammatory+pathways+for+the+prevention+of+preterm+birth.">Pharmacological inhibition of inflammatory pathways for the prevention of preterm birth.</a> Journal Of Reproductive Immunology. 88, 176-184 (2011).</li><li>Voltolini, 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=Understanding+spontaneous+preterm+birth:+from+underlying+mechanisms+to+predictive+and+preventive+interventions.">Understanding spontaneous preterm birth: from underlying mechanisms to predictive and preventive interventions.</a> Reproductive Sciences. 20, 1274-1292 (2013).</li><li>Ratajczak, C. K., Muglia, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insights+into+parturition+biology+from+genetically+altered+mice.">Insights into parturition biology from genetically altered mice.</a> Pediatric research. 64, 581-589 (2008).</li><li>Rajakumar, 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=Placental+HIF-1+alpha,+HIF-2+alpha,+membrane+and+soluble+VEGF+receptor-1+proteins+are+not+increased+in+normotensive+pregnancies+complicated+by+late-onset+intrauterine+growth+restriction.">Placental HIF-1 alpha, HIF-2 alpha, membrane and soluble VEGF receptor-1 proteins are not increased in normotensive pregnancies complicated by late-onset intrauterine growth restriction.</a> American Journal Of Physiology. Regulatory, Integrative And Comparative Physiology. 293, (2007).</li><li>Whitesall, S. E., Hoff, J. B., Vollmer, A. P., D'Alecy, L. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+simultaneous+measurement+of+mouse+systolic+arterial+blood+pressure+by+radiotelemetry+and+tail-cuff+methods.+American+journal+of+physiology.">Comparison of simultaneous measurement of mouse systolic arterial blood pressure by radiotelemetry and tail-cuff methods. American journal of physiology.</a> Heart And Circulatory Physiology. 286, H2408-H2415 (2004).</li><li>Mackay, L. B., Shi, L. B., Maul, H. .., Maner, W. L., Garfield, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+bilateral+pelvic+neurectomy+on+cervical+ripening+in+pregnant+rats.">The effect of bilateral pelvic neurectomy on cervical ripening in pregnant rats.</a> Journal Of Perinatal Medicine. 37, 263-269 (2009).</li><li>Pierce, S. L., Kutschke, W., Cabeza, R., England, S. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+measurement+of+intrauterine+pressure+by+telemetry:+a+new+approach+for+studying+parturition+in+mouse+models.">In vivo measurement of intrauterine pressure by telemetry: a new approach for studying parturition in mouse models.</a> Physiol Genomics. 42, 310-316 (2010).</li><li>Imamura, T., Luedke, C. E., Vogt, S. K., Muglia, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oxytocin+modulates+the+onset+of+murine+parturition+by+competing+ovarian+and+uterine+effects.">Oxytocin modulates the onset of murine parturition by competing ovarian and uterine effects.</a> American Journal Of Physiology. Regulatory, Integrative And Comparative Physiology. 279, R1061-R1067 (2000).</li><li>McCloskey, 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=The+inwardly+rectifying+K++channel+KIR7.1+controls+uterine+excitability+throughout+pregnancy.">The inwardly rectifying K+ channel KIR7.1 controls uterine excitability throughout pregnancy.</a> EMBO Mol Med. 6 (9), 1161-1174 (2014).</li></ol>

The authors have nothing to disclose.

子宮筋層収縮性の調査は、筋肉の緊張のex vivoでの測定値に依存してきた。この方法論は、動物を生きるために投与することができない、新開発の子宮収縮薬の早期テストのために役立ちます。しかし、 生体内でのアプローチは縦方向に労働の進行を理解する必要がある。 in vivoでの測定は、いくつかの目的を果たす。第一に、彼らは妊娠期間にわたって子宮収縮パターン...

早産は、先進国における周産期の罹患率および死亡率の主要な原因である。それは、周産期の罹患率の50％及び周産期死亡率1,2の75％の原因である。早産は多面的で、特発ことができます。多くの研究は、収縮性の一つに、静止組織から子宮筋層を変換する分子的および電気的な経路に浮上しているが、早期陣痛の正確な病態生理学は、とらえどころのないまま。内分泌、炎症、および遺伝子調節はすべて早産3,4に関連している。しかし、倫理的な懸念は、ヒトにおける早産のメカニズムの研究を実施する能力を制限する。 これらの制限を考えると、多くの研究者が分娩の生理学を研究するためにモデル系としてマウスになっている。マウスは、約3週間持続する短い妊娠期間を有し、容易に遺伝子操作することができる。さらに、複数の遺伝的マウスモデルが持っている労働5に不可欠なシグナル伝達経路を決定するために開発されて。マウスとヒトの分娩の主な違いにもかかわらず、マウスとヒトは、子宮内炎症や感染6を含む労働のために不可欠で同じメカニズムの多くを共有しています。このように、マウスは、子宮活動を調べるための貴重なツールとして役立つ。現在までに、マウスでの子宮収縮を測定するためのゴールドスタンダードは、ex vivo等尺性張力の録音されている。しかし、これは実験ごとに1つの妊娠の時点に限定され、その生理的環境から子宮の除去を必要とする。もう一つの重要な要因は、これらの調査のために必要な多数の動物である。最後に、この方法論は、労働と早産病態生理の誘導を調べる長期的な研究のために許可していません。 動脈圧を研究するために使用される放射テレメトリデバイスで行われた最近の進歩は、マウスの7とint型に変更ラット8でrauterine圧力が同じ技術を妊娠中のマウスにおける子宮内圧力の変化を研究するために使用することができるかどうかに疑問を懇願した。初期トラブルシューティングの後、メソッドが成功したマウスでの分娩誘発および進行を測定するために開発された。このin vivoでのアプローチは、強力な陣痛示す高圧状態に静止子宮の低圧状態からの遷移を測定することができる。この方法はまた、遺伝子発現9の生理学的影響を実証する、損なわ分娩および野生型マウスとトランスジェニックマウスの間に有意な圧力差を検出することができた。このプロトコルは、妊娠中のマウス子宮圧力を研究するためのin vivo方法では、リアルタイムで提供する。

<table><tbody><tr><td>Surgical Glue</td><td>3M Vetbond</td><td>1469SB</td><td>Tissue Adhesive--stored in Drierite</td></tr><tr><td>Absorbable 6-0 Sutures</td><td>Ethicon</td><td>J212H</td><td>Vicryl</td></tr><tr><td>Non-absorbable 6-0 Sutures</td><td>Ethicon</td><td>8706H</td><td>Prolene</td></tr><tr><td>Water Jacket Blanket + Heating Pad</td><td>Gaymer</td><td>T/Pump PN 11184-000 Blanket-66N111CC</td><td>Specialized for rodents</td></tr><tr><td>Bead sterilizer</td><td>Keller</td><td>Z378577</td><td>Steri 250 Sterilizer</td></tr><tr><td>Disecting Microscope</td><td>Nikon</td><td>SMZ754</td><td>Fibre optic gooseneck external light source</td></tr><tr><td>Sterile Surgical Gloves--Latex&amp;nbsp;</td><td>Cardinal Health Triflex</td><td>2D7253</td><td></td></tr><tr><td>PhysioTel PA-C10 Pressure Transmitter</td><td>&amp;nbsp;Data Sciences International</td><td>270-0135-001</td><td>TA11PA-C10</td></tr><tr><td>Telemeter Reciever</td><td>&amp;nbsp;Data Sciences International</td><td>272-6001-001</td><td>RPC-1</td></tr><tr><td>Dataquest ART 4.3.2 Analysis Platinum</td><td>&amp;nbsp;Data Sciences International</td><td>271-0147-141</td><td>Analysis software</td></tr><tr><td>Diet Recovery Gel</td><td>Clear H2O</td><td>72-01-5022</td><td>Purified Soft Diet for Rodents</td></tr><tr><td>Tergazyme</td><td>Sigma-Aldrich</td><td>Z273287</td><td>Enzyme detergent</td></tr></tbody></table>

intrauterine telemetry to measure mouse contractile pressure in vivo

分子の電気信号の複雑な統合は、妊娠の終わりに収縮器官に静止子宮を変換するために必要とされる。子宮収縮の重要な調節因子の発見にもかかわらず、このプロセスはまだ十分に理解されていない。トランスジェニックマウスは、分娩を研究するための理想的なモデルを提供する。以前は、マウスに子宮収縮を研究する唯一の方法は、いくつかの理由のために最適ではex vivoでの等尺性張力の録音だった。子宮は、その生理的環境から除去されなければならない、調査の限られた時間的経過が可能であり、マウスを犠牲にしなければならない。放射遠隔測定の最近の開発は、マウスにおけるインビボ子宮内圧の長手方向の、リアルタイム測定を可能にした。送達が記載されるまでここで、子宮内テレメータの注入は、妊娠中期のマウスの子宮内の圧力変化を測定する。プレスの違いを比較することにより野生型およびトランスジェニックマウスとの間の小節がズレ、目的の遺伝子の生理​​的影響を明らかにすることができる。この技術は、早期陣痛を含む妊娠中に子宮筋障害を治療するために使用される治療薬の開発を促進すべきである。

インビボ子宮内圧力のリアルタイムの遠隔収集システムを用いて記録することができる。マウスの同時録画と対に圧力をサンプリングし、各子犬の配達の正確な時間をキャプチャし、母親の子宮内圧力に配達時間を相関させるために使用された。すべてのデータポイントは、圧力対時間プロット（ 図1A）を生成するために記録全体にプロットすることができる。こ?...

Watch this Scientific Journal Video about Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo at JoVE.com

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

This manuscript provides a protocol for implanting telemeters in the mouse for the purpose of measuring intrauterine pressures during pregnancy.

マウス収縮圧力を測定するために子宮内テレメトリ<em&gt;インビボ</em

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. ...

intrauterine-telemetry-to-measure-mouse-contractile-pressure-in-vivo

Research

JoVE Journal

Medicine

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

9.6K ビュー.  Washington University in St. Louis. This manuscript provides a protocol for implanting telemeters in the mouse for the purpose of measuring intrauterine pressures during pregnancy. 

ビデオ: Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

Measuring Left Ventricular Pressure in Late Embryonic and Neonatal Mice

Blood pressure increases significantly during embryonic and postnatal development in vertebrate animals. In the mouse, blood flow is first detectable around embryonic day (E) 8.51. Systolic left ventricular (LV) pressure is 2 mmHg at E9.5 and 11 mmHg at E14.52. At these mid-embryonic stages, the LV is clearly visible through the chest wall for invasive pressure measurements because the ribs and skin are not fully developed. Between E14.5 and birth (approximately E21) imaging methods must be used to view the LV. After birth, mean arterial pressure increases from 30 - 70 mmHg from postnatal day (P) 2 - 353. Beyond P20, arterial pressure can be measured with solid-state catheters (i.e. Millar or Scisense). Before P20, these catheters are too big for developing mouse arteries and arterial pressure must be measured with custom pulled plastic catheters attached to fluid-filled pressure transducers3 or glass micropipettes attached to servo null pressure transducers4.
Our recent work has shown that the greatest increase in blood pressure occurs during the late embryonic to early postnatal period in mice5-7. This large increase in blood pressure may influence smooth muscle cell (SMC) phenotype in developing arteries and trigger important mechanotransduction events. In human disease, where the mechanical properties of developing arteries are compromised by defects in extracellular matrix proteins (i.e. Marfan's Syndrome8 and Supravalvular Aortic Stenosis9) the rapid changes in blood pressure during this period may contribute to disease phenotype and severity through alterations in mechanotransduction signals. Therefore, it is important to be able to measure blood pressure changes during late embryonic and neonatal periods in mouse models of human disease.
We describe a method for measuring LV pressure in late embryonic (E18) and early postnatal (P1 - 20) mice. A needle attached to a fluid-filled pressure transducer is inserted into the LV under ultrasound guidance. Care is taken to maintain normal cardiac function during the experimental protocol, especially for the embryonic mice. Representative data are presented and limitations of the protocol are discussed.

Measuring left ventricular pressure (LV) in embryonic and neonatal mice is described. Pressure is measured by inserting a needle connected to a fluid-filled transducer into the LV under ultrasound guidance. Care must be taken to maintain normal cardiac function during the experimental protocol.

後期胚と新生児マウスの計測左心室圧

Blood pressure increases significantly during embryonic and postnatal development in vertebrate animals. In the mouse, blood flow is first detectable ...

生物工学

Implantation of Radiotelemetry Transmitters Yielding Data on ECG, Heart Rate, Core Body Temperature and Activity in Free-moving Laboratory Mice

The laboratory mouse is the animal species of choice for most biomedical research, in both the academic sphere and the pharmaceutical industry. Mice are a manageable size and relatively easy to house. These factors, together with the availability of a wealth of spontaneous and experimentally induced mutants, make laboratory mice ideally suited to a wide variety of research areas.
In cardiovascular, pharmacological and toxicological research, accurate measurement of parameters relating to the circulatory system of laboratory animals is often required. Determination of heart rate, heart rate variability, and duration of PQ and QT intervals are based on electrocardiogram (ECG) recordings. However, obtaining reliable ECG curves as well as physiological data such as core body temperature in mice can be difficult using conventional measurement techniques, which require connecting sensors and lead wires to a restrained, tethered, or even anaesthetized animal. Data obtained in this fashion must be interpreted with caution, as it is well known that restraining and anesthesia can have a major artifactual influence on physiological parameters1, 2.
Radiotelemetry enables data to be collected from conscious and untethered animals. Measurements can be conducted even in freely moving animals, and without requiring the investigator to be in the proximity of the animal. Thus, known sources of artifacts are avoided, and accurate and reliable measurements are assured. This methodology also reduces interanimal variability, thus reducing the number of animals used, rendering this technology the most humane method of monitoring physiological parameters in laboratory animals3, 4. Constant advancements in data acquisition technology and implant miniaturization mean that it is now possible to record physiological parameters and locomotor activity continuously and in realtime over longer periods such as hours, days or even weeks3, 5.
Here, we describe a surgical technique for implantation of a commercially available telemetry transmitter used for continuous measurements of core body temperature, locomotor activity and biopotential (i.e. onelead ECG), from which heart rate, heart rate variability, and PQ and QT intervals can be established in freeroaming, untethered mice. We also present pre-operative procedures and protocols for post-operative intensive care and pain treatment that improve recovery, well-being and survival rates in implanted mice5, 6.

A surgical technique for implantation of commercially available telemetry transmitters used for continuous measurement of biopotential (one-lead ECG), heart rate, core body temperature and locomotor activity in freely moving mice is shown. Recommendations and protocols for post-operative care and pain relief, improving recovery, well being and survival rate are also presented.

自由に動く実験用マウスの心電図上のデータ、心拍数、体温および活動の要因となるRadiotelemetryトランスミッターの注入

The laboratory mouse is the animal species of choice for most biomedical research, in both the academic sphere and the pharmaceutical industry. Mice are a ...

医学

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 ...

Mouse Maternal Autonomic Changes from Pregnancy to Pup-Rearing

Analysis of Electrocardiograms and Behavior in Mice from Pregnancy to Lactation Period

Changes in the mother-offspring relationship are presumably accompanied by dynamic changes in the autonomic nervous system. Although temporal measurements of autonomic activity have been performed in human mothers and infants, the analysis of long-term changes remains unexplored. Mouse mothers can form social bonds with their pups and have a short period of pregnancy and lactation, which makes them useful for the examination of physiological changes from pregnancy to pup-rearing. Therefore, a telemetry system was used for several weeks to measure the changes in the autonomic nervous system and the behavior of mouse mothers. The current results showed that an electrocardiogram (ECG) could be stably recorded regardless of the movements of mothers and parturition. ECG analysis showed that the heart rate gradually decreased from pregnancy to lactation, and sympathetic activity sharply increased as the pups developed. Furthermore, the simultaneous recording of behavior and ECG in the home cage enabled us to understand the behavior-dependent influences on the ECG, thereby revealing the characteristics of autonomic nervous activity during each behavior. Thus, the present experimental method helps to understand how the physiological characteristics of mothers change from pregnancy through pup rearing, supporting the healthy development of pups.

A simultaneous recording of autonomic activity and detailed maternal behavior of mother mice from pregnancy to lactation was achieved using a telemetry system. This method helps to understand the dynamics of the physiological and behavioral characteristics in mothers from pregnancy to weaning.

Changes in the mother-offspring relationship are presumably accompanied by dynamic changes in the autonomic nervous system. Although temporal measurements ...

行動学

Long-term Blood Pressure Measurement in Freely Moving Mice Using Telemetry

During the development of new vasoactive agents, arterial blood pressure monitoring is crucial for evaluating the efficacy of the new proposed drugs. Indeed, research focusing on the discovery of new potential therapeutic targets using genetically altered mice requires a reliable, long-term assessment of the systemic arterial pressure variation. Currently, the gold standard for obtaining long-term measurements of blood pressure in ambulatory mice uses implantable radio-transmitters, which require&#160;artery cannulation. This technique eliminates the need for tethering, restraining, or anesthetizing the animals which introduce stress and artifacts during data sampling. However, arterial blood pressure monitoring in mice via catheterization can be rather challenging due to the small size of the arteries. Here we present a step-by-step guide to illustrate the crucial key passages for a successful subcutaneous implantation of radio-transmitters and carotid artery cannulation in mice. We also include examples of long-term blood pressure activity taken from freely moving mice after a period of post-surgery recovery. Following this procedure will allow reliable direct blood pressure recordings from multiple animals simultaneously.

The goal of this protocol is to assess systemic blood pressure in conscious freely moving mice using implantable radio-telemetry devices.

テレメトリを使用して自由に動くマウスにおける長期血圧測定

During the development of new vasoactive agents, arterial blood pressure monitoring is crucial for evaluating the efficacy of the new proposed drugs. ...

Application of Consistent Massage-Like Perturbations on Mouse Calves and Monitoring the Resulting Intramuscular Pressure Changes

Massage is generally recognized to be beneficial for relieving pain and inflammation. Although previous studies have reported anti-inflammatory effects of massage on skeletal muscles, the molecular mechanisms behind are poorly understood. We have recently developed a simple device to apply local cyclical compression (LCC), which can generate intramuscular pressure waves with varying amplitudes. Using this device, we have demonstrated that LCC modulates inflammatory responses of macrophages in situ and alleviates immobilization-induced muscle atrophy. Here, we describe protocols for the optimization and application of LCC as a massage-like intervention against immobilization-induced inflammation and atrophy of skeletal muscles of mouse hindlimbs. The protocol that we have developed can be useful for investigating the mechanism underlying beneficial effects of physical exercise and massage. Our experimental system provides a prototype of the analytical approach to elucidate the mechanical regulation of muscle homeostasis, although further development needs to be made for more comprehensive studies.

Here we describe the protocols for applying defined mechanical loads to mouse calves and for monitoring the concomitant intramuscular pressure changes. The experimental systems that we have developed can be useful for investigating the mechanism behind the beneficial effects of physical exercise and massage.

マウス子牛に対する一貫したマッサージ様摂動の適用と、結果として生じる筋肉内圧変化のモニタリング

Massage is generally recognized to be beneficial for relieving pain and inflammation. Although previous studies have reported anti-inflammatory effects of ...

免疫・感染学

Implantation of Combined Telemetric ECG and Blood Pressure Transmitters to Determine Spontaneous Baroreflex Sensitivity in Conscious Mice

Blood pressure (BP) and heart rate (HR) are both controlled by the autonomic nervous system (ANS) and are closely intertwined due to reflex mechanisms. The baroreflex is a key homeostatic mechanism to counteract acute, short-term changes in arterial BP and to maintain BP in a relatively narrow physiological range. BP is sensed by baroreceptors located in the aortic arch and carotid sinus. When BP changes, signals are transmitted to the central nervous system and are then communicated to the parasympathetic and sympathetic branches of the autonomic nervous system to adjust HR. A rise in BP causes a reflex decrease in HR, a drop in BP causes a reflex increase in HR.
Baroreflex sensitivity (BRS) is the quantitative relationship between changes in arterial BP and corresponding changes in HR. Cardiovascular diseases are often associated with impaired baroreflex function. In various studies reduced BRS has been reported in e.g., heart failure, myocardial infarction, or coronary artery disease. 
Determination of BRS requires information from both BP and HR, which can be recorded simultaneously using telemetric devices. The surgical procedure is described beginning with the insertion of the pressure sensor into the left carotid artery and positioning of its tip in the aortic arch to monitor arterial pressure followed by the subcutaneous placement of the transmitter and ECG electrodes. We also describe postoperative intensive care and analgesic management. After a two-week period of post-surgery recovery long-term ECG and BP recordings are performed in conscious and unrestrained mice. Finally, we include examples of high-quality recordings and the analysis of spontaneous baroreceptor sensitivity using the sequence method.

The baroreflex is a heart-rate regulation mechanism by the autonomic nervous system in response to blood-pressure changes. We describe a surgical technique to implant telemetry transmitters for continuous and simultaneous measurement of electrocardiogram and blood pressure in mice. This can determine spontaneous baroreflex sensitivity, an important prognostic marker for cardiovascular disease.

意識のあるマウスにおける自発的な圧反射感受性を決定するための遠隔ECGと血圧伝達器の組み合わせの埋め込み

Blood pressure (BP) and heart rate (HR) are both controlled by the autonomic nervous system (ANS) and are closely intertwined due to reflex mechanisms. ...

Real-Time Electrocardiogram Monitoring During Treadmill Training in Mice

Regular physical exercise is a major contributor to cardiovascular health, influencing various metabolic as well as electrophysiological processes. However, in certain cardiac diseases such as inherited arrhythmia syndromes, e.g., arrhythmogenic cardiomyopathy (ACM) or myocarditis, physical exercise may have negative effects on the heart leading to a proarrhythmogenic substrate production. Currently, the underlying molecular mechanisms of exercise-related proarrhythmogenic remodeling are largely unknown, thus it remains unclear which frequency, duration, and intensity of exercise can be considered safe in the context of disease(s).
The proposed method allows to study proarrhythmic/antiarrhythmic effects of physical exercise by combining treadmill training with real-time monitoring of the ECG. Implantable telemetry devices are used to continuously record the ECG of freely moving mice over a period of up to 3 months both at rest and during treadmill training. Data acquisition software with its analysis modules is used to analyze basic ECG parameters such as heart rate, P wave duration, PR interval, QRS interval, or QT duration at rest, during and after training. Furthermore, heart rate variability (HRV) parameters and occurrence of arrhythmias are evaluated. In brief, this manuscript describes a step-by-step approach to experimentally explore exercise induced effects on cardiac electrophysiology, including potential proarrhythmogenic remodeling in mouse models.

Electrocardiogram (ECG) is the key variable to understanding cardiac electrophysiology. Physical exercise has beneficial effects but may also be harmful in the context of cardiovascular diseases. This manuscript provides a method of recording real-time ECG during exercise, which can serve to investigate its effects on cardiac electrophysiology in mice.

マウスのトレッドミルトレーニング中のリアルタイム心電図モニタリング

Regular physical exercise is a major contributor to cardiovascular health, influencing various metabolic as well as electrophysiological processes. ...

Ex Vivo Method for Assessing the Mouse Reproductive Tract Spontaneous Motility and a MATLAB-based Uterus Motion Tracking Algorithm for Data Analysis

Dysmenorrhea, or painful cramping, is the most common symptom associated with menses in females and its severity can hinder women&#39;s everyday lives. Here, we present an easy and inexpensive method that would be instrumental for testing new drugs decreasing uterine contractility. This method utilizes the unique ability of the entire mouse reproductive tract to exhibit spontaneous motility when maintained ex vivo in a Petri dish containing oxygenated Krebs buffer. This spontaneous motility resembles the wave-like myometrial activity of the human uterus, referred to as endometrial waves. To demonstrate the effectiveness of the method, we employed a well-known uterine relaxant drug, epinephrine. We demonstrate that the spontaneous motility of the entire mouse reproductive tract can be quickly and reversibly inhibited by 1 &#181;M epinephrine in this Petri dish model. Documenting the changes of uterine motility can be easily done using an ordinary smart phone or a sophisticated digital camera. We developed a MATLAB-based algorithm allowing motion tracking to quantify spontaneous uterine motility changes by measuring the rate of uterine horn movements. A major advantage of this ex vivo approach is that the reproductive tract remains intact throughout the entire experiment, preserving all intrinsic intrauterine cellular interactions. The major limitation of this approach is that up to 10-20% of uteri may exhibit no spontaneous motility. Thus far, this is the first quantitative ex vivo method for assessing spontaneous uterine motility in a Petri dish model.

Uterine contractions are important for the well-being of females. However, pathologically increased contractility may result in dysmenorrhea, especially in younger females. Here, we describe a simple ex vivo preparation allowing quick assessment of the efficacy of smooth muscle relaxants that may be used for treating dysmenorrhea.

マウス生殖管自発的運動性を評価するためのEx Vivo法とデータ解析のためのMATLABベースの子宮運動追跡アルゴリズム

Dysmenorrhea, or painful cramping, is the most common symptom associated with menses in females and its severity can hinder women&#39;s everyday lives. ...

生物学

Continuous Telemetric In Utero Tracheal Pressure Measurements in Fetal Lambs

Normal in utero lung development and growth rely upon the expansion of airspaces and the controlled efflux of lung liquid into the amniotic space. Infants with congenital diaphragmatic hernia (CDH) also have lung hypoplasia due to occupation of the chest cavity by the stomach and bowel and, in the most severe cases, the liver. Balloon tracheal occlusion reduces the severity of lung hypoplasia in fetuses with CDH but increases the risk of premature birth. Understanding the optimal occlusion pressure and duration required to improve lung hypoplasia with tracheal occlusion is essential to improving in utero corrective treatments for CDH. The study reports a new method for continuous measurement of the intratracheal and amniotic pressures in an unoccluded and occluded fetal lamb surgical model of CDH. Time-pregnant Merino ewes underwent two recovery hysterotomies: the first at ~80 days of gestation to create the CDH, and the second at ~101 days of gestation to occlude the fetal trachea and implant an intratracheal and amniotic pressure measurement device. Lambs were delivered at ~142 days, and the pressure measurement device was removed and cleaned. The data were downloaded and filtered using a 6 h window. Transrespiratory pressure was calculated.

<meta charset="utf8"></head><body>胎児の子羊における子宮内連続テレメトリー気管圧測定

Optimization of occlusion pressure and duration required to improve lung hypoplasia with tracheal occlusion is essential to improve in utero corrective treatments for congenital diaphragmatic hernia (CDH). This study reports a new method for continuous measurement of the tracheal pressure in an occluded and unoccluded fetal lamb surgical model of CDH.

胎児の子羊における 子宮内 連続テレメトリー気管圧測定

Normal in utero lung development and growth rely upon the expansion of airspaces and the controlled efflux of lung liquid into the amniotic space. Infants ...

マウス収縮圧力を測定するために子宮内テレメトリ

要約

さらに動画を探す

この動画の章

後期胚と新生児マウスの計測左心室圧

自由に動く実験用マウスの心電図上のデータ、心拍数、体温および活動の要因となるRadiotelemetryトランスミッターの注入

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

Analysis of Electrocardiograms and Behavior in Mice from Pregnancy to Lactation Period

テレメトリを使用して自由に動くマウスにおける長期血圧測定

マウス子牛に対する一貫したマッサージ様摂動の適用と、結果として生じる筋肉内圧変化のモニタリング

意識のあるマウスにおける自発的な圧反射感受性を決定するための遠隔ECGと血圧伝達器の組み合わせの埋め込み

マウスのトレッドミルトレーニング中のリアルタイム心電図モニタリング

マウス生殖管自発的運動性を評価するためのEx Vivo法とデータ解析のためのMATLABベースの子宮運動追跡アルゴリズム

胎児の子羊における子宮内連続テレメトリー気管圧測定

マウス収縮圧力を測定するために子宮内テレメトリ

要約

さらに動画を探す

この動画の章

後期胚と新生児マウスの計測左心室圧

自由に動く実験用マウスの心電図上のデータ、心拍数、体温および活動の要因となるRadiotelemetryトランスミッターの注入

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

Analysis of Electrocardiograms and Behavior in Mice from Pregnancy to Lactation Period

テレメトリを使用して自由に動くマウスにおける長期血圧測定

マウス子牛に対する一貫したマッサージ様摂動の適用と、結果として生じる筋肉内圧変化のモニタリング

意識のあるマウスにおける自発的な圧反射感受性を決定するための遠隔ECGと血圧伝達器の組み合わせの埋め込み

マウスのトレッドミルトレーニング中のリアルタイム心電図モニタリング

マウス生殖管自発的運動性を評価するためのEx Vivo法とデータ解析のためのMATLABベースの子宮運動追跡アルゴリズム

胎児の子羊における 子宮内 連続テレメトリー気管圧測定

胎児の子羊における子宮内連続テレメトリー気管圧測定