我们感谢弗雷德·罗伯茨和克里斯白色为典型的技术支持。我们感谢布里格姆妇女医院心血管生理学核心，提供与仪器和资金用于这项工作。这项工作是由NHLBI支持部分补助HL093148，HL086967和HL 088533（RL），K99HL107642和埃里森基金会（SC）。

外科手术<ol><li>获得8个周龄雄性C57BL / 6小鼠，并适应了一个星期的任何实验程序执行之前。 </li><li>在此之前成像，肺动脉闭塞为依据AVMA指引先前描述14执行并通过IACUC协议。 超声心动图图像采集与测量 所用的所有缩写都总结在表1中 。 </li></ol> 1。胸骨旁长轴（PLAX）M模式查看获取RV真空室尺寸，短轴缩短率（FS），以及露营壁厚<ol><li>采用B模式设置，以获得一个完整的胸骨旁左室长轴切面。与动物躺在平台上的仰卧位置（见注6.1和6.2），逆时针方向上的动物的位置的40 MHz的超声波探头（MS550D）与约30°角，与槽口指向尾端方向的左胸骨旁线（ <strong&gt;图1A）。由稍微倾斜沿探针（ 图1D）的y轴以获得在屏幕中央一个完整的低压腔心切面调整探头角度。 </li><li>一旦正确的地标（RV，低压，中压，鳌，LA）所示图2A和2B清晰可见，切换到M模式。指示线会显示在M模式设定在屏幕上。该生产线应定位鳌使用为标志（ 图2A和B）要经过房车室的最宽部分。 </li><li>这种观点认为，房车壁和室间隔应清晰可见。请确保焦点深度在于RV室的中心。记录与电影存储的数据进行测量房车室的尺寸，FS和RV壁厚下线。的M模式图像的例子示于图2C和2D。 （见注6.3）。 </li></ol> 2。胸骨旁短轴切面在中间乳头水平，以获得面积变化率（FAC） <ol><li>从上面（ 图1A）中描述的位置，切换到B模式，把探头顺时针旋转90°得到胸骨旁短轴切面（ 图1B）。尖探针稍微沿着探针的x轴，以防止胸骨阻塞性视图。 </li><li>晃动上下沿探针的y轴，以获得中等水平乳头状（见注6.4）。 </li><li>在此视图中，乳头肌通常位于在2和5时的位置（ 图3）。 </li></ol> 3。胸骨旁短轴切面在主动脉瓣电平（右PSAX主动脉级）获取RV壁厚和PA峰值速度<ol><li>从上面（ 图1B）中描述的位置，移动探针在y轴朝向颅骨直到主动脉瓣剖面图显示在该窗口的中间。 </li><li>右室流出吨RACT（RVOT）应该是可见的顶部为一个月牙形的结构与三尖瓣分离RA的房车作为如图4A和2 B。用电影商店RV壁厚离线测量记录数据。 （见注6.5）。 </li><li>保持在相同的位置。 （见注6.6）。 </li><li>切换到彩色多普勒模式和位置​​PW-虚线平行于流动的容器中的方向上的黄色的线。注意，蓝色和红色的颜色表示流远离和朝向所述探针，分别为（ 图4C和图4 D）。 </li><li>将光标PW在肺动脉瓣叶尖端。用电影存储（见注6.7。）记录数据。测量PA的峰值速度下线。 </li></ol> 4。修改胸骨旁长轴房车和PA的视图获取PA的峰值速度<ol><li>继续基于B模式设置，定位探头（MS550D或MS250）到右胸骨旁线（ 图1C），并慢慢标题探针约30-45在探头（ 图1D）对小鼠的胸部，以清楚地看到在PA跨越主动脉所示，在图的y轴°角5A和5 B。 </li><li>切换到彩色多普勒模式和位置PW-虚线平行于流动的容器中（ 图5C和5 D）的方向上的黄色的线。将光标PW在肺动脉瓣叶尖端。用电影存储（见注6.6。）记录数据和测量PA的峰值速度下线。 </li></ol> 5。数据计算与分析<ol><li> RV壁厚可从（协议3）如上述从房车PSAX主动脉水平得到B模式的数据进行计算。选择2D区域跟踪工具来跟踪RV墙的面积舒张（如图中红色区域， 如图6）。然后，使用该距离跟踪工具跟踪RVOT的壁的内圆周和外圆周（如图所示在图6的蓝线）。采取的内外周的平均值。用公式<img fo:content-width="0.8in" src="/files/ftp_upload/51041/RVW_Thickness.jpg" width="80px" /> ，我们计算RV墙（RVW）的厚度。 （见注6.8）。 </li><li>对于其他标准的参数，请参考手册从各自的制造商能够进行数据分析。 </li></ol> 6。笔记<ol><li>所有图像都使用VEVO 2100系统中收集。类似的图像，可以使用超声波成像系统其他制造商获得，以及各种超声仪器的相对利弊，先前已经比较8,12,15。建议所有的图片应该以双盲的方式尽可能获得和分析。 </li><li>选择合适的麻醉，如短ð吸入异氟烷（2-3％诱导，和1.0％，以维持）的掩膜是至关重要的心脏跳动的维持在正常生理评分（大于500次/分钟），使我们能够检测可再现的和一致的基底和升高的肺动脉在这个研究中收缩压。 </li><li>确保收集在尽可能高的帧率可以将数据（&gt; 200帧/秒）。 </li><li>寻找具有最大腔尺寸的视图。 </li><li>阻塞是由于肋骨和胸骨主要是由于房车的胸骨位置，是获得优良图像成像房车的这种方法的一个最大的障碍。通过重新定位的动物或探针，操作者可以克服胸骨块，将获得对RV的必要的视图。这可能需要从5-15分钟，这取决于动物的生理机能。 </li><li>您可能需要切换探头MS250因为MS550D探头可用于假和小鼠的PAC前和40 MHz的探头是能够记录峰值速度300-1500米/秒，而MS250是能够捕捉到园区速度可达4,000 mm /秒。 </li><li>可以接受的是具有一个探头角度小于20°，PA的峰值速度的精确测量。 </li><li> RV墙厚度和面积/尺寸一致的测量是使用多个声窗制作，无论在长期和短轴。一些这些窗口的选择将取决于操作者的经验，并可以解释的变异可能是分担不同的统计结果。 </li></ol>

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没有什么可以透露。

我们证明，TTE为RV的结构和功能在小鼠的常规评估一个敏感的和可再现的方法。 TTE的出现之前，房车的研究主要是通过正确的心脏导管插入术，终端和入侵的程序6,9,11,17专注于右室收缩压测量。 此前报道已经描述了多种技术来执行正确的心脏测量3,4,11,17-19。然而，大多数以往的研究报道房车大小，并在主要是定性而非定量的方式5的结构数据。房车评?...

从历史上看，心脏衰竭预后评估的重点是LV的，这是通过超声心动图容易想像。使用超声心动图左室结构和功能众多的研究已经导致建立对左室结构正常价值和功能1,5,6。从二维及彩色多普勒图像获得左室大小和收缩功能的测量是非常重要的，因为它们允许车厢和几何形状非常详细的视觉划分为LV 7。 M-模式通常用于在小鼠中测定的LV尺寸和短轴缩短率（FS）。跨观察员和内部观察员变异较低，使用这种模式的直径测量，但壁厚测量往往是相当变量7。脉冲多普勒彩色（PW或彩色多普勒）已经被用来评估瓣膜返流8,9。 类似于LV，右室起着重要的作用，是一个显著predictor发病率和死亡率在患者患有心肺疾病1,7,10的。然而，房车的超声心动图评价本质上是具有挑战性的，由于其形状复杂5,11和胸骨位置，阻止了超声波8,9。 RV是围绕着LV的一个月牙形状的结构包裹，并具有复杂的解剖结构壁薄是习惯于低的压力和阻力，以肺血管6。以克服升高的血管阻力（PVR），右心室第一尺寸增大并发生肥大。在慢性疾病，如肺动脉高压或肺血管疾病，房车经过逐步扩张，最终导致心脏收缩和舒张功能4,5,10的恶化。 超声心动图起着筛选和PAH的诊断具有重要的作用，尽管目前在临床诊断能力一定的局限性。的主要优点TTE在于它是无创性，并且它可以进行对轻度镇静，甚至是有意识的动物9。 TTE还提供了PA的压力的合理估计，以及改变在房车的结构和功能12,13的持续评估。由于TTE的技术进步，其中包括高频机械探针的发展，使得在5-12毫米，高帧率（大于300帧/秒），和高采样率的深度约50微米的轴向分辨率，超声心动图是一种选择工具，成像快速萎缩小型小鼠心脏8,11。 纵向监测使用多个视图，包括二维（2D）和短长轴，M型和多普勒声学窗口右心室功能的提供房车解剖结构和功能的补充信息。总的来说，这种方法允许在生理和病理的设置RV血流动力学的完整的纵向评估<suP&gt; 4,7。 在此，我们提供了使用无创TTE表征房车和解剖小鼠继发PAC功能变化的详细一步一步的方法。

<table border="0" cellpadding="0" cellspacing="0" width="609">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="61">
			<td height="61" style="height:61px;width:157px;">High Frequency Ultrasound</td>
			<td style="width:108px;">FUJIFILM VisualSonics, Inc.</td>
			<td style="width:96px;">Vevo 2100</td>
			<td style="width:248px;"></td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:157px;">High-frequency Mechanical Transducer</td>
			<td style="width:108px;">FUJIFILM VisualSonics, Inc.</td>
			<td style="width:96px;">MS250, MS550D, MS400</td>
			<td style="width:248px;"></td>
		</tr>
		<tr height="67">
			<td height="67" style="height:67px;width:157px;">Millar Mikro Pressure Catheter</td>
			<td style="width:108px;">Millar</td>
			<td style="width:96px;">SPR-1000</td>
			<td style="width:248px;"></td>
		</tr>
	</tbody>
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assessment of right ventricular structure and function in mouse model of pulmonary artery constriction by transthoracic echocardiography

新兴的临床数据支持这一概念，RV功能障碍是心血管疾病和心脏衰竭1-3的发病机制是至关重要的。另外，RV被显著肺疾病如肺动脉高压（PAH）的影响。另外，RV是显着敏感的心肌病变，包括左心室（LV）功能不全，心脏瓣膜病或RV梗死4。了解RV的心脏疾病的发病机制中的作用，可靠和非侵入性的方法，在结构上和功能上访问RV是必不可少的。 无创性经胸超声心动图（TTE）的方法建立和验证在成年小鼠监测RV结构和功能的动态变化。施加压力的RV，我们采用的肺动脉收缩（PAC）手术模型，并采用了高频率的超声显微成像测量超过7天期间的房车响应制度。假手术小鼠作为对照。图片是在浅麻醉小鼠获得的基线（手术前），第0天（马上手术后），3天，第7天（手术后）。数据是用软件离线分析。 几个声窗（B，M，及彩色多普勒模式），它可以在小鼠体内进行持续获得，允许RV结构（包括房车壁厚度，舒张末期和收缩末期尺寸）的可靠和可重复的测量，和功能（面积变化率，短轴缩短率，PA峰值速度和峰值压力梯度）在正常小鼠和下面的PAC。 使用这种方法时，压力梯度从PAC得到的是精确地测量在实时使用彩色多普勒模式和媲美用Millar的高保真微尖导管进行直接的压力测量。总而言之，这些数据表明，从各种并发症得到RV测量使用超声心动图imentary意见是可靠，重复性好，可以提供关于房车的结构和功能的见解。这种方法将有助于更好地了解房车心功能不全的作用。

在这项研究中，基线超声心动图进行48小时前，手术。将小鼠随机分为两组。小鼠接受肺动脉闭塞（PAC）和假手术（Sham组）。在0天，第3和7以下的外科手术进行超声心动图。动物立即处死后，最后超声心动图和心脏标本进行组织学评估。导管是在亚组（n = 3时和2为0天和第7天，分别）PAC小鼠通过压力导管来测量RVSP的进行。 获得的所有图像数据进行分析脱机。重要的是，超声?...

Watch this Scientific Journal Video about Assessment of Right Ventricular Structure and Function in Mouse Model of Pulmonary Artery Constriction by Transthoracic Echocardiography at JoVE.com

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

右心室（RV）的功能障碍是心血管疾病的发病机制中的关键的，但有限的方法可用于它的评估。在超声成像的最新进展提供了一种无创，准确的选择纵向房车研究。在此，我们用详细的RV压力超负荷小鼠模型一步一步的超声心动图的方法。

右心室结构和功能的肺动脉缩窄经胸超声小鼠模型的评估

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

assessment-right-ventricular-structure-function-mouse-model-pulmonary

Research

JoVE Journal

Medicine

27.4K 次观看.  Harvard Medical School. 右心室（RV）的功能障碍是心血管疾病的发病机制中的关键的，但有限的方法可用于它的评估。在超声成像的最新进展提供了一种无创，准确的选择纵向房车研究。在此，我们用详细的RV压力超负荷小鼠模型一步一步的超声心动图的方法。 

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

Transthoracic Echocardiography in Mice

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene expression. Transgenic and gene targeting methods can be used to generate mice with altered cardiac size and function,1-3 and as a result, in vivo techniques are needed to evaluate their cardiac phenotype. Transthoracic echocardiography, pulse wave Doppler (PWD), and tissue Doppler imaging (TDI) can be used to provide dimensional measurements of the mouse heart and to quantify the degree of cardiac systolic and diastolic performance. Two-dimensional imaging is used to detect abnormal anatomy or movements of the left ventricle, whereas M-mode echo is used for quantification of cardiac dimensions and contractility.4,5 In addition, PWD is used to quantify localized velocity of turbulent flow,6 whereas TDI is used to measure the velocity of myocardial motion.7 Thus, transthoracic echocardiography offers a comprehensive method for the noninvasive evaluation of cardiac function in mice.

Transthoracic echocardiography offers a noninvasive method for the evaluation of cardiac function in mice. A combination of ultrasound and Doppler imaging modalities can be used to obtain dimensional measurements of the heart and intracardiac blood flow, which together provide an assessment of cardiac systolic and diastolic performance.

经胸超声心动图在小鼠

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

科研

医学

Echocardiographic Assessment of the Right Heart in Mice

Transgenic and toxic models of pulmonary arterial hypertension (PAH) are widely used to study the pathophysiology of PAH and to investigate potential therapies. Given the expense and time involved in creating animal models of disease, it is critical that researchers have tools to accurately assess phenotypic expression of disease. Right ventricular dysfunction is the major manifestation of pulmonary hypertension. Echocardiography is the mainstay of the noninvasive assessment of right ventricular function in rodent models and has the advantage of clear translation to humans in whom the same tool is used. Published echocardiography protocols in murine models of PAH are lacking.
In this article, we describe a protocol for assessing RV and pulmonary vascular function in a mouse model of PAH with a dominant negative BMPRII mutation; however, this protocol is applicable to any diseases affecting the pulmonary vasculature or right heart. We provide a detailed description of animal preparation, image acquisition and hemodynamic calculation of stroke volume, cardiac output and an estimate of pulmonary artery pressure.

This article provides a protocol for the echocardiographic assessment of right ventricular size and pulmonary hypertension in mice. Applications include phenotype determination and serial assessment in transgenic and toxin-induced mouse models of cardiomyopathy and pulmonary vascular disease.

右心小鼠的超声心动图评价

Transgenic and toxic models of pulmonary arterial hypertension (PAH) are widely used to study the pathophysiology of PAH and to investigate potential ...

Chronic Thromboembolic Pulmonary Hypertension and Assessment of Right Ventricular Function in the Piglet

An original piglet model of Chronic Thromboembolic Pulmonary Hypertension (CTEPH) associated with chronic Right Ventricular (RV) dysfunction is described. Pulmonary Hypertension (PH) was induced in 3-week-old piglets by a progressive obstruction of the pulmonary vascular bed. A ligation of the left Pulmonary Artery (PA) was performed first through a mini-thoracotomy. Second, weekly embolizations of the right lower pulmonary lobe were done under fluoroscopic guidance with n-butyl-2-cyanoacrylate during 5 weeks. Mean Pulmonary Arterial Pressure (mPAP) measured by ritght heart catheterism, increased progressively, as well as Right Atrial pressure and Pulmonary Vascular Resistances (PVR) after 5 weeks compared to sham animals. Right Ventricular (RV) structural and functional remodeling were assessed by transthoracic echocardiography (RV diameters, RV wall thickness, RV systolic function). RV elastance and RV-pulmonary coupling were assessed by Pressure-Volume Loops (PVL) analysis with conductance method. Histologic study of the lung and the right ventricle were also performed. Molecular analyses on RV fresh tissues could be performed through repeated transcutaneous endomyocardial biopsies. Pulmonary microvascular disease in obstructed and unobstructed territories was studied from lung biopsies using molecular analyses and pathology. Furthermore, the reliability and the reproducibility was associated with a range of PH severity in animals. Most aspects of the human CTEPH disease were reproduced in this model, which allows new perspectives for the understanding of the underlying mechanisms (mitochondria, inflammation) and new therapeutic approaches (targeted, cellular or gene therapies) of the overloaded right ventricle but also pulmonary microvascular disease.

Chronic Thromboembolic Pulmonary Hypertension (CTEPH) and Right Ventricular (RV) dysfunction were induced in piglets by progressive obstruction of the pulmonary arteries. Consequences were remarkably similar to those observed in CTEPH patients. This animal model would be a very useful tool for pathophysiology and therapeutic experiments on CTEPH and RV failure.

慢性血栓栓塞性肺动脉高压和右心室功能的仔猪评估

An original piglet model of Chronic Thromboembolic Pulmonary Hypertension (CTEPH) associated with chronic Right Ventricular (RV) dysfunction is described. ...

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.

经胸斑点跟踪超声心动图左室心肌变形的定量评价

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，主动脉和肺动脉的超声心动图小鼠

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

A Pulmonary Trunk Banding Model of Pressure Overload Induced Right Ventricular Hypertrophy and Failure

Right ventricular (RV) failure induced by sustained pressure overload is a major contributor to morbidity and mortality in several cardiopulmonary disorders. Reliable and reproducible animal models of RV failure are therefore warranted in order to investigate disease mechanisms and effects of potential therapeutic strategies. Banding of the pulmonary trunk is a common method to induce isolated RV hypertrophy but in general, previously described models have not succeeded in creating a stable model of RV hypertrophy and failure.
We present a rat model of pressure overload induced RV hypertrophy caused by pulmonary trunk banding (PTB) that enables different phenotypes of RV hypertrophy with and without RV failure. We use a modified ligating clip applier to compress a titanium clip around the pulmonary trunk to a pre-set inner diameter. We use different clip diameters to induce different stages of disease progression from mild RV hypertrophy to decompensated RV failure.
RV hypertrophy develops consistently in rats subjected to the PTB procedure and depending on the diameter of the applied banding clip, we can accurately reproduce different disease severities ranging from compensated hypertrophy to severe decompensated RV failure with extra-cardiac manifestations.
The presented PTB model is a valid and robust model of pressure overload induced RV hypertrophy and failure that has several advantages to other banding models including high reproducibility and the possibility of inducing severe and decompensated RV failure.

We present a surgical method to induce right ventricular hypertrophy and failure in rats.

压力超载诱发右室肥厚和衰竭的肺动脉扣条柱模型

Right ventricular (RV) failure induced by sustained pressure overload is a major contributor to morbidity and mortality in several cardiopulmonary ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

用线 Myography 测定小鼠肠系膜动脉的等轴收缩力

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

Invasive Hemodynamic Assessment for the Right Ventricular System and Hypoxia-Induced Pulmonary Arterial Hypertension in Mice

Pulmonary arterial hypertension (PAH) is a chronic and severe cardiopulmonary disorder. Mice are a popular animal model used to mimic this disease. However, the evaluation of right ventricular pressure (RVP) and pulmonary artery pressure (PAP) remains technically challenging in mice. RVP and PAP are more difficult to measure than left ventricular pressure because of the anatomical differences between the left and right heart systems. In this paper, we describe a stable right heart hemodynamic measurement method and its validation using healthy and PAH mice. This method is based on open-chest surgery and mechanical ventilation support. It is a complicated procedure compared to closed chest procedures. While a well-trained surgeon is required for this surgery, the advantage of this procedure is that it can generate both RVP and PAP parameters at the same time, so it is a preferable procedure for the evaluation of PAH models.

Here, we present a protocol to perform an invasive hemodynamic assessment of the right ventricle and pulmonary artery in mice using an open-chest surgery approach.

小鼠右心室系统及缺氧诱发肺动脉高血压的侵入性血液动力学评估

Pulmonary arterial hypertension (PAH) is a chronic and severe cardiopulmonary disorder. Mice are a popular animal model used to mimic this disease. ...

Morphological and Functional Assessment of the Right Ventricle Using 3D Echocardiography

Traditionally, it was believed that the right side of the heart has a minor role in circulation; however, more and more data suggest that right ventricular (RV) function has strong diagnostic and prognostic power in various cardiovascular disorders. Due to its complex morphology and function, assessment of the RV by conventional two-dimensional echocardiography is limited: the everyday clinical practice usually relies on simple linear dimensions and functional measures. Three-dimensional (3D) echocardiography overcame these limitations by providing volumetric quantification of the RV free of geometrical assumptions. Here, we offer a step-by-step guide to obtain and analyze 3D echocardiographic data of the RV using the leading commercially available software. We will quantify 3D RV volumes and ejection fraction. Several technical aspects may help to improve the quality of RV acquisition and analysis as well, which we present in a practical manner. We review the current opportunities and the limiting factors of this method and also highlight the potential applications of 3D RV assessment in current clinical practice.

Here, we provide a step-by-step acquisition and analysis protocol for the 3D volumetric assessment of the right ventricle, mainly focusing on the practical aspects that maximize the feasibility of this technique.

使用3D超声心动图对右心室进行形态学和功能评估

Traditionally, it was believed that the right side of the heart has a minor role in circulation; however, more and more data suggest that right ...

Generation and Characterization of Right Ventricular Myocardial Infarction Induced by Permanent Ligation of the Right Coronary Artery in Mice

Right ventricular infarction (RVI) is a common presentation in clinical practice. Severe RVI can lead to fatal hemodynamic dysfunction and arrhythmia. In contrast to the extensively used mouse myocardial infarction (MI) model generated by left coronary artery ligation, the RVI mouse model is rarely employed due to the difficulty associated with model generation. Research on the mechanisms and treatment of RVI-induced RV remodeling and dysfunction requires animal models to mimic the pathophysiology of RVI in patients. This study introduces a feasible procedure for RVI model generation in C57BL/6J mice. Further, this model was characterized based on the following: infarct size evaluation at 24 h after MI, assessment of cardiac remodeling and function with echocardiography, RV hemodynamics assessment, and histology of the infarct zone at 4 weeks after RVI. In addition, a coronary vasculature cast was performed to observe the coronary arterial arrangement in RV. This mouse model of RVI would facilitate the research on mechanisms of right heart failure and seek new therapeutic targets of RV remodeling.

There are several differences between the right and left ventricles. However, the pathophysiology of right ventricular infarction (RVI) has not been clarified. In the present protocol, a reproducible method for RVI mouse model generation is introduced, which may provide a means to explain the mechanism of RVI.

小鼠右冠状动脉永久结扎诱导的右心室性心肌梗死的生成与表征

Right ventricular infarction (RVI) is a common presentation in clinical practice. Severe RVI can lead to fatal hemodynamic dysfunction and arrhythmia. In ...