著者は博士に感謝します。 DMT圧力ミオグラフとDRSを使用するためのポール黄とドミトリAtochin。高脂肪食または標準食を与えたマウスを提供するためのBinglan Yuとチョンレイ。 資金源この作品は、ハーバードメディカルスクール（ESに買収）から医学学者サイエンティスト開発米国心臓協会（ESに買収）からグラント10SDG2610313、とエレノアとマイルズショア50周年記念フェローシッププログラムによってサポートされていました。

1。溶液の調製<ol><li> 500X EDTAストック：500mgのEDTA- の Na 2•2H 2 Oを比較検討し、50ミリリットルの脱イオン水に溶解する。室温で保管してください。 </li><li>塩化カリウムは、ソリューションを脱分極。 <ol><li> 3.69グラムのNaCl、18.64グラムのKCl、0.36グラム硫酸マグネシウム無水、0.41グラムのKH 2 PO 4、0.46グラムのCaCl 2•2H 2 O：K10Xストック溶液を調製250ミリリットルの脱イオン水に溶解する。室温で保管してください。 </li><li>ソリューション1Xを脱分極100ミリリットル最終のKClの場合：90ミリリットル脱イオン水0.21のNaHCO 3、0.18グラムのブドウ糖を溶かす。 K10X原液10mlのを追加します。 500X EDTA溶液95μLを加える。よく混ぜる。 4℃で保存一週間以内にご使用ください。 </li></ol></li><li>実験の日（1リットル用）に新鮮なHEPES-PSS溶液を調製。 <ol><li> 6.96グラムのNaCl、0.35グラムのKCl、0.288グラムし、MgSO 4·7H 2 O•、0.1605グラムKH 2 PO 4、2.38グラムHEPES。 100mlに溶解する脱イオン水。フラスコAとマーク</li><li> 0.312グラムのCaCl 2•2H 2 O脱イオン水100mlに溶解する。フラスコBとしてマーク</li><li> 1.25グラムのNaHCO 3、0.991グラムのブドウ糖。 98ミリリットルの脱イオン水に溶解する。フラスコC.としてマーク</li></ol></li><li> C.大きなフラスコ内の700ミリリットルの脱イオン水を取るフラスコ中500X EDTA 2 mlを加え。連続ボルテックス大きなフラスコにフラスコA、BおよびCの内容を注ぐ。 NaOHでpHを7.4に調整する。 </li></ol> 2。使用される薬剤<ol><li>フェニレフリン（10 -2 M）：10ミリリットルの脱イオン水に20.37ミリグラム溶かす。 -80アリコート1ミリリットルと店舗℃の直列実験の日に、10 -3、10 -4、10 -5〜10 -6モル/ Lを得るために希釈する。 </li><li>アセチルコリン（10 -2 M）：10ミリリットルの脱イオン水に18.17ミリグラム溶かす。 -80アリコート1ミリリットルと店舗℃のシリアル10 -3、10 -4、10 -5及び10 -6を得るために希釈する実験当日のモル/ L。 </li></ol> 3。マウス男性WTとsGCα1 - / - S6とB6の背景にマウスがこの研究を通して検討した。 sGCα1 - / -は4,5前述のように作製した。実験動物（マウス）を含むハウジングと手順はマサチューセッツ総合病院、ボストン、マサチューセッツ州の研究動物のケアに小委員会によって承認された。 4。腸間膜動脈における血管反応性の測定<ol><li> （200 mg / kg体重、腹腔内）ペントバルビタールでマウスを安楽死させる。腹腔を開き、腸間膜組織を解剖する。分離し、解剖結合および脂肪組織の自由3次の腸間膜動脈、および95％O 2/15分間、5％CO 2で予め平衡化し、氷冷HEPES-PSS溶液中の動脈を置く。無腸間から分岐して2〜3ミリメートルの長さのリングをカット動脈。血管内に血液が存在しない場合ミクロ血管レベルで動脈と静脈を区別することは問題である。したがって、我々はそれを解剖前に動物でまだそのままである一方、血管を識別をお勧めします。 </li><li>入口および出口弁を通しての10ml注射器の助けを借りて、HEPES-PSS溶液を用いて圧力ミオグラフ室（DMTモデル110P＆11Pバージョン1.31、 図2）におけるガラスカニューレに記入します。過度の圧力がカニューレに接続されている脆弱なトランスデューサーを破損する恐れがあるので、カニューレの充填を穏やかにし、慎重に行う必要があります。充填後カニューレはしっかり入口と出口バルブの両方を閉じます。 </li><li>右カニューレに容器の一方の端を取り付け、慎重にナイロン縫合糸の一つ細かい鎖とそれを結ぶ。注射器の助けを借りて、入口弁経由HEPES溶液を容器にフラッシュと記入。近い容器に左のカニューレに持参し、その上に容器のもう一方の端をマウントします。ナイロン縫合糸でそれを結ぶ。埋めるHEPES溶液で10ミリリットルまでとチャンバー。優しく注射器の助けを借りて、入口弁を介しHEPES溶液を押すことで漏れをチェックします。 </li><li>ミオグラフで、ビデオカメラの下でチャンバーをインストールします。チャンバー内の酸素や熱（37℃）を起動します。バルブが閉じている間、第HEPES液リザーバからチューブP1と入口弁を接続する。チューブ内に気泡がなくなるまで、チューブを介して任意のバブルとソリューションパスしましょう​​。バルブを開きます。 </li><li>チューブP2は圧力調整器から来るとチャンバーの左バルブを接続します。任意の気泡を再度確認してください。全体のシステム内の任意の気泡や漏れがあってはいけません。 </li><li>ミオインターフェイスパネル上またはソフトウェア内の圧力メニューに移動し、流れをOFFしながらポンプをONにしてください。 </li><li>プログラムを開いて、COLLECTをクリックします。容器（ 図3）現在画面に表示されるべきである。容器はmonitoriを可能にする、顕微鏡に取り付けられたカメラで可視化されるngのと血管腔、血管径、肉厚の分析。 </li><li>徐々にミオ - インターフェイスパネルまたはプログラムのP1の圧力を選択することにより、P1バルブ経由interluminal圧力を高め、次のように圧力値を入力します。5 mmHgの→10→20→40→60 mmHgの。容器はいつか圧力が増加している間にねじったり畳み込むする傾向;テンションを調整したり、垂直または縦マイクロポジショナー（ 図2）の助けを借りて、それに応じて負担。 60 mmHgので容器を平衡化し、37℃45分間、少なくとも。平衡時に予め温めHEPESで一度浴溶液を変更します。 </li><li>のKCl脱分極溶液10mlを適用し、完全に平滑筋細胞を脱分極および最大収縮を達成するために浴に、37℃で温め。安定したくびれた後、HEPES溶液3回、10分ごとにバスをすすいでください。 </li><li>安定して再現することにより内皮の血管と整合性の実行可能性を確認してくださいフェニレフリンの添加（10 -5 M）およびアセチルコリンへ撓応答（10 -5 M）。 HEPES溶液ごとに10分で3回すすいでください。 </li><li> -容器preconstrict、安定したくびれが得られた場合に、アセチルコリンの増加する用量（10 -9、3×10の逐次添加によって累積濃度血管拡張応答曲線（CRC）を実行するフェニレフリン（10 -5 M）を追加9、10 -8、3×10 -8、10 -7、3×10 -7、10 -6、3×10 -6および10 -5 M）。最終投与後、10分ごとに新しいCRCを開始する前にHEPES溶液で3回すすいでください。 </li><li> 2mMのEGTAを含むCa 2 +のフリーPSSを適用することにより、受動的な内腔の直径を決定します。すべてのパラメータを計算するために使用される各用量反応のための記録されたトレーシング対策ルーメン径（ 図4）から。 </li><li> PERCとしてすべてのアセチルコリン弛緩応答を表現以下の式を用いてフェニレフリン収縮後のカルシウムフリー直径と直径、の違いと比べてフェニレフリンpreconstriction後の内腔直径entageの変更： </li><li>パーセンテージ拡張= 100％X [（D X - D I）/（Dカルシウムフリー - D I）]、ここで、Dは測定された内腔直径およびXは、私であり、CA送料アゴニストの各用量で動脈の直径を表す（x）は、初期の直径以下はくびれは、（i）、およびCa 2 +を含まないバッファ（CA-無料）フェニレフリン。 </li></ol> 5。統計分析すべての連続測定は、平均±SEMとして表される。腸間膜動脈の血管反応性を反復測定の双方向分散分析によって分析される。すべての場合において、P &lt;0.05は統計的に有意であると考えられる。

<ol>
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著者らは、開示することは何もありません。

マウスは一部であるため、それによって人間の病態生理のためのマウスモデルを生成する遺伝子改変を導入する可能性があるため、多くの研究者のための選択の実験モデルである。血管小さい抵抗の状態ではなく、より大きな導管血管のは、主に脈管系11を通して血流の調節を画定する。マウスのような小動物の抵抗動脈、のサイズが微小血管の機能を研究するためのワイヤミオグラ...

圧力ミオグラフシステムは小動脈、静脈及び他の血管の生理学的機能および特性を測定するために使用される。動脈または静脈の無傷の小セグメントは、2つの小さなガラスカニューレに取り付けられ、槽がインビボ特性（ 図1および2）のの大部分を維持することができ、適切な内腔の圧力に加圧される。圧力ミオグラフにおける生理学的状態の近くに孤立血管の本質的な性質（ 例えば筋トーン）の調査を可能にする、血管床の生体内挙動に反映されます。筋収縮力変換装置1への直接の機械的結合によって評価されるワイヤ筋運動記録法、過圧力筋運動記録法の利点のいくつかは、血管系で開発された全体の抵抗を定義するマイクロ抵抗動脈が、一方で、検討することができる（i）を含むワイヤーミオグラフは大きい導管動脈、（ⅱ）Tに限定されているまだワイヤが（iii）の容器の自然な形状が良好に維持される、血管内腔を通過する必要がないので、内皮細胞に損傷を与えるハット危険性が低減され、および（iv）した船舶寸法は、広範囲ので学ぶことができる圧力やせん断応力2。 微細血管を勉強することは、高血圧などの心血管疾患で、変更された血管緊張に貢献病態と分子メカニズムを理解するために大規模な導管動脈の勉強よりも有益なことができます。例えば、8週間のマウスに高脂肪食を供給するに関連付けられている血管内皮機能障害はなく、大動脈輪で2 回オーダー腸間膜動脈を3（ 図3）で実証することができます。圧力筋運動記録法の別の利点は、加圧容器の固有筋収縮が存在することであり、この現象内皮の役割と機能について検討することができる。ここでは、DESCR損なわれた一酸化窒素（NO）-cGMPのシグナリングの設定でマウスの腸間膜3次抵抗動脈の血管反応性を研究するために、圧力ミオグラフの使用をIBE。

<table border="1">
		<tbody>
		 <tr>
			<td>Name</td>
			<td>Company</td>
			<td>Cataloge No.</td>
		 </tr>
		 <tr>
			<td>NaCl</td>
			<td>Fisher Scientific</td>
			<td>BP358</td>
		 </tr>
		 <tr>
			<td>CaCl2 (2H2O)</td>
			<td>Fisher Scientific</td>
			<td>C79-500</td>
		 </tr>
		 <tr>
			<td>KCl</td>
			<td>Sigma</td>
			<td>P9333</td>
		 </tr>
		 <tr>
			<td>MgSO4 </td>
			<td>Fisher Scientific</td>
			<td>M65-500</td>
		 </tr>
		 <tr>
			<td>KH2PO4 </td>
			<td>Sigma</td>
			<td>P3786</td>
		 </tr>
		 <tr>
			<td>NaHCO3 </td>
			<td>Fisher Scientific</td>
			<td>BP328</td>
		 </tr>
		 <tr>
			<td>NaOH</td>
			<td>Fisher Scientific</td>
			<td>S318</td>
		 </tr>
		 <tr>
			<td>D-Glucose</td>
			<td>Sigma</td>
			<td>G8270</td>
		 </tr>
		 <tr>
			<td>EDTA</td>
			<td>Fisher Scientific</td>
			<td>BP121</td>
		 </tr>
		 <tr>
			<td>HEPES</td>
			<td>Sigma</td>
			<td>H3375</td>
		 </tr>
		 <tr>
			<td>Phenylephrine</td>
			<td>Acros Organics</td>
			<td>AC20724</td>
		 </tr>
		 <tr>
			<td>Acetylcholine</td>
			<td>Sigma</td>
			<td>A6625</td>
		 </tr>
		 <tr>
			<td>Pressure Myograph System</td>
			<td>DMT</td>
			<td></td>
		 </tr>
		</tbody>
 </table>

assessing murine resistance artery function using pressure myography

圧力ミオグラフシステムは、適切な経壁圧に加小動脈の機能評価、で絶妙に便利です。圧力筋運動記録法で達成近い生理状態は血管床の生体内挙動に外挿することができる薬理学的および生理学的な刺激に固有の応答の詳細な特性評価を可能にします。圧力ミオグラフは、従来のワイヤmyographsに比べていくつかの利点を有する。例えば、小さい抵抗容器はしっかりと制御され、生理学的に適切な管腔内の圧力で研究することができる。ここでは、アセチルコリンに反応して血管リラックスするフェニレフリンで前収縮させた3次腸間膜動脈（長い3〜4ミリメートル）、、の能力を研究しています。腸間膜動脈を60 mmHgで一定の圧力に維持される加圧されてシールされたシステムに接続された2つのカニューレに取り付けられている。脈管の内腔と外径がcontinuouあるずるそうはそれぞれ、フェニレフリンおよびアセチルコリンに反応して血管収縮と血管弛緩のリアルタイム定量化を可能にし、ビデオカメラを用いて記録した。 心血管疾患の病因を研究するために、圧力筋運動記録法の適用可能性を実証するため、我々は、全身性高血圧症のマウスモデルにおける内皮依存性血管機能を評価した。可溶性グアニル酸シクラーゼ（ - / - sGCα1）のα1サブユニット欠損マウスは時129S6（S6）背景（sGCα1 -/-S6）に高血圧ですが、ないときはC57BL / 6（B6）背景（sGCαに1 -/-B6）。圧力筋運動記録法を用いて、障害内皮依存性血管弛緩におけるsGCα1欠乏の結果のことを示しています。血管の機能不全は、おそらくcontributisGCα1 -/-B6マウスよりsGCα1 -/-S6においてより顕著であるsGCα1 -/-B6マウスよりsGCα1 -/-S6が高い血圧にNG。 圧力筋運動記録法により、心血管疾患のメカニズムに私達の洞察力を増強、血管の収縮と弛緩に様々な刺激の効果を評価するために使用することができ、比較的簡単ですが、高感度かつ機構的に有用な技術である。

NOは集中人間6および動物モデル7の両方で血圧の恒常性の維持に関与していません。血管平滑筋の弛緩を制御するNOの能力は、可溶性グアニル酸シクラーゼ（sGCの）、cGMPの8を生成ヘム含有ヘテロ酵素によって媒介される。近年、血圧修飾遺伝的変異は、ヒト9の血圧を調節するのsGCの関連性を示す、sGCα1およびsGCβ1遺伝子を含む遺伝子座の同定...

Watch this Scientific Journal Video about Assessing Murine Resistance Artery Function Using Pressure Myography at JoVE.com

Assessing Murine Resistance Artery Function Using Pressure Myography

圧力筋運動記録法では、容器の無傷の小セグメントは、2つの小さなカニューレに取り付けられて、適切な内腔の圧力に加圧した。ここでは、マウス3の血管弛緩応答を測定する方法を説明<sup&gt; RD</supC57とsGCαで&gt;オーダー腸間膜動脈<sub&gt; 1</sub<sup&gt; - / -</sup&gt;圧力筋運動記録法を用いたマウス。

圧力筋運動記録法を用いたマウス抵抗動脈機能を評価

Pressure myograph systems are  exquisitely useful in the functional assessment of small arteries, pressurized  to a suitable transmural pressure. The  ...

assessing-murine-resistance-artery-function-using-pressure-myography

Research

JoVE Journal

Biology

21.9K ビュー.  Massachusetts General Hospital, Harvard Medical School. 圧力筋運動記録法では、容器の無傷の小セグメントは、2つの小さなカニューレに取り付けられて、適切な内腔の圧力に加圧した。ここでは、マウス3の血管弛緩応答を測定する方法を説明 RDオーダー腸間膜動脈 1

ビデオ: Assessing Murine Resistance Artery Function Using Pressure Myography

Measuring Blood Pressure in Mice using Volume Pressure Recording, a Tail-cuff Method

The CODA 8-Channel High Throughput Non-Invasive Blood Pressure system measures the blood pressure in up to 8 mice or rats simultaneously. The CODA tail-cuff system uses Volume Pressure Recording (VPR) to measure the blood pressure by determining the tail blood volume. A specially designed differential pressure transducer and an occlusion tail-cuff measure the total blood volume in the tail without the need to obtain the individual pulse signal. Special attention is afforded to the length of the occlusion cuff in order to derive the most accurate blood pressure readings. VPR can easily obtain readings on dark-skinned rodents, such as C57BL6 mice and is MRI compatible. The CODA system provides you with measurements of six (6) different blood pressure parameters; systolic and diastolic blood pressure, heart rate, mean blood pressure, tail blood flow, and tail blood volume. Measurements can be made on either awake or anesthetized mice or rats. The CODA system includes a controller, laptop computer, software, cuffs, animal holders, infrared warming pads, and an infrared thermometer. There are seven different holder sizes for mice as small as 8 grams to rats as large as 900 grams.

The CODA 8-Channel High Throughput Non-Invasive Blood Pressure system measures the blood pressure in up to 8 mice or rats simultaneously. This tail-cuff system uses Volume Pressure Recording (VPR) to measure the blood pressure by determining the tail blood volume.

ボリューム圧力記録、テールカフ法を用いたマウスにおける測定血圧

The CODA 8-Channel High Throughput Non-Invasive Blood Pressure system measures the blood pressure in up to 8 mice or rats simultaneously. The CODA ...

生物学

Bioassays for Monitoring Insecticide Resistance

Pest resistance to pesticides is an increasing problem because pesticides are an integral part of high-yielding production agriculture. When few products are labeled for an individual pest within a particular crop system, chemical control options are limited. Therefore, the same product(s) are used repeatedly and continual selection pressure is placed on the target pest. There are both financial and environmental costs associated with the development of resistant populations. The cost of pesticide resistance has been estimated at approximately $ 1.5 billion annually in the United States. This paper will describe protocols, currently used to monitor arthropod (specifically insects) populations for the development of resistance. The adult vial test is used to measure the toxicity to contact insecticides and a modification of this test is used for plant-systemic insecticides. In these bioassays, insects are exposed to technical grade insecticide and responses (mortality) recorded at a specific post-exposure interval. The mortality data are subjected to Log Dose probit analysis to generate estimates of a lethal concentration that provides mortality to 50% (LC50) of the target populations and a series of confidence limits (CL's) as estimates of data variability. When these data are collected for a range of insecticide-susceptible populations, the LC50 can be used as baseline data for future monitoring purposes. After populations have been exposed to products, the results can be compared to a previously determined LC50 using the same methodology.

This manuscript demonstrates and discusses techniques used to survey pesticide susceptibility and detect resistance to contact and systemic pesticides in arthropod pests.

モニタリングの殺虫剤抵抗性のためのバイオアッセイ

Pest resistance to pesticides is an increasing problem because pesticides are an integral part of high-yielding production agriculture. When few products ...

Exploring Arterial Smooth Muscle Kv7 Potassium Channel Function using Patch Clamp Electrophysiology and Pressure Myography

Contraction or relaxation of smooth muscle cells within the walls of resistance arteries determines the artery diameter and thereby controls flow of blood through the vessel and contributes to systemic blood pressure. The contraction process is regulated primarily by cytosolic calcium concentration ([Ca2+]cyt), which is in turn controlled by a variety of ion transporters and channels. Ion channels are common intermediates in signal transduction pathways activated by vasoactive hormones to effect vasoconstriction or vasodilation. And ion channels are often targeted by therapeutic agents either intentionally (e.g. calcium channel blockers used to induce vasodilation and lower blood pressure) or unintentionally (e.g. to induce unwanted cardiovascular side effects).
Kv7 (KCNQ) voltage-activated potassium channels have recently been implicated as important physiological and therapeutic targets for regulation of smooth muscle contraction. To elucidate the specific roles of Kv7 channels in both physiological signal transduction and in the actions of therapeutic agents, we need to study how their activity is modulated at the cellular level as well as evaluate their contribution in the context of the intact artery.
The rat mesenteric arteries provide a useful model system. The arteries can be easily dissected, cleaned of connective tissue, and used to prepare isolated arterial myocytes for patch clamp electrophysiology, or cannulated and pressurized for measurements of vasoconstrictor/vasodilator responses under relatively physiological conditions. Here we describe the methods used for both types of measurements and provide some examples of how the experimental design can be integrated to provide a clearer understanding of the roles of these ion channels in the regulation of vascular tone.

Measurements of Kv7 (KCNQ) potassium channel activity in isolated arterial myocytes (using patch clamp electrophysiological techniques) in parallel with measurements of constrictor/dilator responses (using pressure myography) can reveal important information about the roles of Kv7 channels in vascular smooth muscle physiology and pharmacology.

パッチクランプ電気生理学および圧力筋運動記録法を用いた動脈平滑筋KV7カリウムチャネル機能を探る

Contraction  or relaxation of smooth muscle cells within the walls of resistance arteries  determines the artery diameter and thereby controls flow of ...

RNA Secondary Structure Prediction Using High-throughput SHAPE

Understanding the function of RNA involved in biological processes requires a thorough knowledge of RNA structure. Toward this end, the methodology dubbed "high-throughput selective 2' hydroxyl acylation analyzed by primer extension", or SHAPE, allows prediction of RNA secondary structure with single nucleotide resolution. This approach utilizes chemical probing agents that preferentially acylate single stranded or flexible regions of RNA in aqueous solution. Sites of chemical modification are detected by reverse transcription of the modified RNA, and the products of this reaction are fractionated by automated capillary electrophoresis (CE). Since reverse transcriptase pauses at those RNA nucleotides modified by the SHAPE reagents, the resulting cDNA library indirectly maps those ribonucleotides that are single stranded in the context of the folded RNA. Using ShapeFinder software, the electropherograms produced by automated CE are processed and converted into nucleotide reactivity tables that are themselves converted into pseudo-energy constraints used in the RNAStructure (v5.3) prediction algorithm. The two-dimensional RNA structures obtained by combining SHAPE probing with in silico RNA secondary structure prediction have been found to be far more accurate than structures obtained using either method alone.

High-throughput selective 2' hydroxyl acylation analyzed by primer extension (SHAPE) utilizes a novel chemical probing technology, reverse transcription, capillary electrophoresis and secondary structure prediction software to determine the structures of RNAs from several hundred to several thousand nucleotides at single nucleotide resolution.

ハイスループットSHAPEを使用したRNA二次構造予測

Understanding the function of RNA involved in biological processes requires a thorough knowledge of RNA structure. Toward this end, the methodology dubbed ...

Assessing Cerebral Autoregulation via Oscillatory Lower Body Negative Pressure and Projection Pursuit Regression

The process by which cerebral perfusion is maintained constant over a wide range of systemic pressures is known as &#8220;cerebral autoregulation.&#8221; Effective dampening of flow against pressure changes occurs over periods as short as ~15 sec and becomes progressively greater over longer time periods. Thus, slower changes in blood pressure are effectively blunted and faster changes or fluctuations pass through to cerebral blood flow relatively unaffected. The primary difficulty in characterizing the frequency dependence of cerebral autoregulation is the lack of prominent spontaneous fluctuations in arterial pressure around the frequencies of interest (less than ~0.07 Hz or ~15 sec). Oscillatory lower body negative pressure (OLBNP) can be employed to generate oscillations in central venous return that result in arterial pressure fluctuations at the frequency of OLBNP. Moreover, Projection Pursuit Regression (PPR) provides a nonparametric method to characterize nonlinear relations inherent in the system without a priori assumptions and reveals the characteristic non-linearity of cerebral autoregulation. OLBNP generates larger fluctuations in arterial pressure as the frequency of negative pressure oscillations become slower; however, fluctuations in cerebral blood flow become progressively lesser. Hence, the PPR shows an increasingly more prominent autoregulatory region at OLBNP frequencies of 0.05 Hz and below (20 sec cycles). The goal of this approach it to allow laboratory-based determination of the characteristic nonlinear relationship between pressure and cerebral flow and could provide unique insight to integrated cerebrovascular control as well as to physiological alterations underlying impaired cerebral autoregulation (e.g., after traumatic brain injury, stroke, etc.).

Cerebral perfusion is maintained across a range of pressures via cerebral autoregulation. However, characterizing autoregulation requires prominent pressure fluctuations at regulated frequencies. The described protocol will show how oscillatory lower body negative pressure can generate pressure fluctuations to provide data for projection pursuit regression for quantification of the autoregulatory curve.

振動下半身陰圧と射影追跡回帰を経由して脳自己調節を評価する

The process by which cerebral perfusion is maintained constant over a wide range of systemic pressures is known as &#8220;cerebral autoregulation.&#8221; ...

Measuring Respiratory Function in Mice Using Unrestrained Whole-body Plethysmography

Respiratory dysfunction is one of the leading causes of morbidity and mortality in the world and the rates of mortality continue to rise. Quantitative assessment of lung function in rodent models is an important tool in the development of future therapies. Commonly used techniques for assessing respiratory function including invasive plethysmography and forced oscillation. While these techniques provide valuable information, data collection can be fraught with artefacts and experimental variability due to the need for anesthesia and/or invasive instrumentation of the animal. In contrast, unrestrained whole-body plethysmography (UWBP) offers a precise, non-invasive, quantitative way by which to analyze respiratory parameters. This technique avoids the use of anesthesia and restraints, which is common to traditional plethysmography techniques. This video will demonstrate the UWBP procedure including the equipment set up, calibration and lung function recording. It will explain how to analyze the collected data, as well as identify experimental outliers and artefacts that results from animal movement. The respiratory parameters obtained using this technique include tidal volume, minute volume, inspiratory duty cycle, inspiratory flow rate and the ratio of inspiration time to expiration time. UWBP does not rely on specialized skills and is inexpensive to perform. A key feature of UWBP, and most appealing to potential users, is the ability to perform repeated measures of lung function on the same animal.

The assessment of respiratory physiology has traditionally relied upon techniques, which require restraint or sedation of the animal. Unrestrained whole-body plethysmography, however, provides precise, non-invasive, quantitative analysis of respiratory physiology in animal models. In addition, the technique allows repeated respiratory assessment of mice allowing for longitudinal studies.

拘束されていない全身プレチスモグラフィを使用したマウスにおける呼吸機能の測定

Respiratory dysfunction is one of the leading causes of morbidity and mortality in the world and the rates of mortality continue to rise. Quantitative ...

Cardiac Pressure-Volume Loop Analysis Using Conductance Catheters in Mice

Cardiac pressure-volume loop analysis is the &#8220;gold-standard&#8221; in the assessment of load-dependent and load-independent measures of ventricular systolic and diastolic function. Measures of ventricular contractility and compliance are obtained through examination of cardiac response to changes in afterload and preload. These techniques were originally developed nearly three decades ago to measure cardiac function in large mammals and humans. The application of these analyses to small mammals, such as mice, has been accomplished through the optimization of microsurgical techniques and creation of conductance catheters. Conductance catheters allow for estimation of the blood pool by exploiting the relationship between electrical conductance and volume. When properly performed, these techniques allow for testing of cardiac function in genetic mutant mouse models or in drug treatment studies. The accuracy and precision of these studies are dependent on careful attention to the calibration of instruments, systematic conduct of hemodynamic measurements and data analyses. We will review the methods of conducting pressure-volume loop experiments using a conductance catheter in mice.

Cardiac pressure-volume loop analysis is the most comprehensive way to measure cardiac function in the intact heart. We describe a technique to perform and analyze cardiac pressure volume loops, using conductance catheters.

マウスにおけるコンダクタンスカテーテルを用いて心臓圧力 - 体積ループ解析

Cardiac pressure-volume loop analysis is the &#8220;gold-standard&#8221; in the assessment of load-dependent and load-independent measures of ventricular ...

Intracavernosal Pressure Recording to Evaluate Erectile Function in Rodents

Erectile dysfunction (ED) is defined as the inability to attain or keep an erection of the penis, and this has become a prevalent male sexual disorder. Rodents are employed by many studies to research the physiology/pathology of erectile function. Erectile function in rodents can be evaluated by measuring the intracavernosal pressure (ICP). In practice, ICP can be monitored following electrical stimulation of the cavernous nerves (CNs). The arterial pressure of the carotid artery (the mean arterial pressure) is used as the reference for ICP. Using ICP recording protocols, many key parameters of erectile function can be measured from the ICP response curve. The ICP measurement provides more information than the apomorphine-induced penile erection test, and is cheaper than telemetric monitoring of the corpus spongiosum penis, making this method the most popular one to evaluate erectile function. However, compared to the easily-performed APO-induced erectile function test, successful ICP recordings require attention to detail, practice, and adherence to the operation method. In this work, an introduction to ICP recording in rats is provided to complement the procedure efficiently.

Intracavernosal pressure recording (ICP) is an important method to evaluate the erectile function of experimental animals. Here, a detailed protocol is demonstrated for the recording procedure of ICP by catheterizing the crura penis and then electrically stimulating the cavernous nerves in rats.

齧歯動物で勃起機能評価 Intracavernosal 圧記録

Erectile dysfunction (ED) is defined as the inability to attain or keep an erection of the penis, and this has become a prevalent male sexual disorder. ...

Induction of Right Ventricular Failure by Pulmonary Artery Constriction and Evaluation of Right Ventricular Function in Mice

The mechanism of right ventricular failure (RVF) requires clarification due to the uniqueness, high morbidity, high mortality, and refractory nature of RVF. Previous rat models imitating RVF progression have been described. Compared with rats, mice are more accessible, economical, and widely used in animal experiments. We developed a pulmonary artery constriction (PAC) approach which is comprised of banding the pulmonary trunk in mice to induce right ventricular (RV) hypertrophy. A special surgical latch needle was designed that allows for easier separation of the aorta and the pulmonary trunk. In our experiments, the use of this fabricated latch needle reduced the risk of arteriorrhexis and improved the surgical success rate to 90%. We used different padding needle diameters to precisely create quantitative constriction, which can induce different degrees of RV hypertrophy. We quantified the degree of constriction by evaluating the blood flow velocity of the PA, which was measured by noninvasive transthoracic echocardiography. RV function was precisely evaluated by right heart catheterization at 8 weeks after surgery. The surgical instruments made inhouse were composed of common materials using a simple process that is easy to master. Therefore, the PAC approach described here is easy to imitate using instruments made in the lab and can be widely used in other labs. This study presents a modified PAC approach that has a higher success rate than other models and an 8-week postsurgery survival rate of 97.8%. This PAC approach provides a useful technique for studying the mechanism of RVF and will enable an increased understanding of RVF.

Here, we provide a useful approach for studying the mechanism of right ventricular failure. A more convenient and efficient approach to pulmonary artery constriction is established using surgical instruments made inhouse. In addition, methods to evaluate the quality of this approach by echocardiography and catheterization are provided.

肺動脈収縮による右心室障害の誘導とマウスにおける右心室機能の評価

The mechanism of right ventricular failure (RVF) requires clarification due to the uniqueness, high morbidity, high mortality, and refractory nature of ...

Performing In Vivo and Ex Vivo Electrical Impedance Myography in Rodents

Electrical impedance myography (EIM) is a convenient technique that can be used in preclinical and clinical studies to assess muscle tissue health and disease. EIM is obtained by applying a low-intensity, directionally focused, electrical current to a muscle of interest across a range of frequencies (i.e., from 1 kHz to 10 MHz) and recording the resulting voltages. From these, several standard impedance components, including the reactance, resistance, and phase, are obtained. When performing ex vivo measurements on excised muscle, the inherent passive electrical properties of the tissue, namely the conductivity and relative permittivity, can also be calculated. EIM has been used extensively in animals and humans to diagnose and track muscle alterations in a variety of diseases, in relation to simple disuse atrophy, or as a measure of therapeutic intervention. Clinically, EIM offers the potential to track disease progression over time and to assess the impact of therapeutic interventions, thus offering the opportunity to shorten the clinical trial duration and reduce sample size requirements. Because it can be performed noninvasively or minimally invasively in living animal models as well as humans, EIM offers the potential to serve as a novel translational tool enabling both preclinical and clinical development. This article provides step-by-step instructions on how to perform in vivo and ex vivo EIM measurements in mice and rats, including approaches to adapt the techniques to specific conditions, such as for use in pups or obese animals.

Performing In Vivo and Ex Vivo Electrical Impedance Myography in Rodents

This article details how to perform in vivo (using surface and needle electrode arrays) and ex vivo (using a dielectric cell) electrical impedance myography on the rodent gastrocnemius muscle. It will demonstrate the technique in both mice and rats and detail the modifications available, (i.e., obese animals, pups).

げっ歯類における in vivoおよび ex vivo 電気インピーダンス筋電視検査の実行

Electrical impedance myography (EIM) is a convenient technique that can be used in preclinical and clinical studies to assess muscle tissue health and ...