The study was supported by the Swiss National Foundation [SNF 310030-149986 to MNG], the University of Fribourg, and Fribourg Hospital.

所有的动物在符合欧洲公约动物保健收到人文关怀。获得国家兽医局，弗里堡，瑞士联邦兽医办公室，瑞士批准同意后按照瑞士动物保护法进行外科手术。 1.心收获注:所有手术干预措施，异氟烷麻醉下进行的。作出了努力，以减少动物的痛苦。特别是，所有动物接受0.1毫克/千克丁丙诺啡预麻醉的皮下注射。外科协议诱导心肌梗塞先前已在别处13中所述。 <ol><li>麻醉（插管动物，2.5％异氟烷麻醉适当通过爪子捏反射确认）下一个的心肌梗死的动物进行胸骨。 <ol><li>通过切割皮肤，然后肌肉打开动物用手术剪。削减左，右肋骨，然后取出胸部。 </li><li>删除以前的手术（LAD结扎）后剩余的粘连。切开主动脉并取出心脏。把在1M氯化钾（在PBS中）的组织，然后用PBS清洗。 </li></ol></li></ol> 2.组织准备<ol><li>把梗死心脏在纵向的丙烯酸大鼠心脏矩阵。保持在-20℃1小时。 </li><li>直接使用具有横向刀片矩阵切心脏。确保每片厚2毫米。切割约5 - 为每个心脏（基于重构级）7滑动;这就是所谓的系统抽样。 </li><li>在此步骤中，执行2,3,5-氯化三苯基四唑（TTC）染色是可选的（保持心脏切片基站至顶点的方向）。 <ol><li>在37℃孵育，在PBS中的1％TTC 50分钟。孵育它在4％低聚甲醛（PFA）进行20分钟至1小时。把部分betweeÑ与2-毫米间隔物的两块玻璃板和拍照与15X放大率耦合有相机的体视显微镜。 警告！多聚甲醛是有毒的。 </li></ol></li><li>幻灯冻结（ 第一选择） <ol><li>把每个幻灯片在塑料模具（10×10×5毫米）的带安装为cryotomy介质（最佳切割温度，OCT）保持取向（放置部的面向顶点侧倒在模具的底部）。冷冻液态氮冷却10下与2-甲基丁烷蒸气块 - 15分钟。最后，保存在-80℃的组织。 </li></ol></li><li>石蜡化（ 第二选项） <ol><li>放置在包埋盒的每个滑板（通过将部分向下在盒的底部的面向顶点侧保持的取向），然后在4％PFA 24小时。把它放在纸巾处理器的机器过夜。 <ol><li>孵育它在乙醇中的70％2小时。孵育它伊桑醇95％2小时。孵育它在乙醇100％，持续3小时。孵育它在二甲苯4小时。孵育它在石蜡（熔融在60℃下在烘箱中）5小时。最后，通过嵌入在石蜡每个心脏幻灯片制作块。 </li></ol></li></ol></li></ol> 3.马森Goldner三色染色<ol><li>使从石蜡块组织切片用手动切片（厚度:5微米），或从OCT块设置为-18℃的低温恒温器（厚度:7微米）。 </li><li>从染色心脏各部分一张幻灯片每只大鼠（3 -每张幻灯片4横向剖面的）用Masson-Goldner三色染色（ 见附件 ）。 注:这一步的石蜡切片开始。 <ol><li>熔化在60℃下将载玻片在烘箱。根据通风橱，deparaffinize它们二甲苯两次，每次10分钟。水化它们在100％乙醇，95％乙醇，70％乙醇和蒸馏水对每个3分钟。 注:从这一步骤的开始冰冻切片秒。 </li><li>解决这些问题的解决方案，布安一夜之间。然后，冲洗他们在流动的自来水10 - 15分钟。冲洗他们在蒸馏水中。孵育他们在Mayer的苏木3分钟。 </li><li>删除的幻灯片，让他们在蒸馏水中5分钟。然后，孵育它们在酸性品红-丽春5分钟。冲洗他们在1％乙酸1分钟。 </li><li>其次，培养他们磷钼酸橙G 1分钟。冲洗他们在1％乙酸，1分钟，孵育它们在光绿色染料10分钟，并冲洗它们在1％乙酸1分钟。 </li><li>脱水它们在70％的乙醇（30秒），95％的乙醇（30秒），和100％的乙醇（5分钟）。放在组织切片的树脂封固剂一滴，用盖玻片覆盖他们，让他们干。 </li></ol></li></ol> 4.梗死大小分析<ol><li>来自再加上相机立体显微镜（放大15倍），每张幻灯片获得一个图像。照片统治者具有相同的设置秒。 </li><li>使用图像分析软件来测量梗塞，隔膜的厚度，左心室（LV）腔区域，该梗塞区域，使用LV组织区域的中间疤痕的厚度。 <ol><li>设定标尺图像（ 图1A）的规模。 <ol><li>点击测量 ，然后选择设置转换系数 。绘制校准栏上的一条线。右键点击图片，然后点击结束校准 。注意栏值，然后单击确定 。 </li></ol></li><li>从染色心脏的图像（ 图1B）的LV。使用多段工具。选择LV逐点，然后右键单击 复制/粘贴的任何地方。 </li><li>采用单段测量工具测量瘢痕及室间隔厚度（ 图1C </st荣&gt;）。 </li><li>自动检测的LV腔，梗塞，以及使用在RGB模式（ 图1D）的自动区域测量工具的LV面积。 <ol><li>点击工具。 仅激活边框和 连续 RGB模式。最后，点击所关注的区域内检测到它。如有必要，使用精密工具。 </li></ol></li></ol></li><li>计算梗塞大小作为梗塞面积与左心室面积的比率。 </li><li>计算膨胀指数如下:[LV腔面积/整个LV面积] / [梗塞厚度/隔膜厚度]，与整个LV区域包括了LV腔和LV组织区域。 </li><li>最后，如下计算每个心脏一个"平均":从幻灯片梗死扩张平均指数] * [梗死幻灯片数/总幻灯片的数量。 </li></ol>

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The authors have nothing to disclose.

该议定书中的关键步骤 纤维组织可在使用心脏收获和图像的系统抽样一种慢性心肌梗死大鼠模型准确地评估分析从基地获得到顶点三色染色组织切片。两个步骤是成功的协议实现尤为重要。首先，对于心脏收获使用氯化钾使心肌以松弛状态被维持。本步骤是从不同的心梗塞尺寸的比较重要的。第二，在布安溶液中的部分的过夜固定是至关重要的，以获得明亮的?...

心肌梗死（MI）是全球死亡和残疾的主要原因。冠状动脉心脏疾病是主要原因; MI缺血连续冠脉事件，如阻塞造成的。当未在第一6小时内进行再灌注，局部缺血诱导的不可逆的心肌坏死。在患者中，心肌梗死的表征依赖于不同的诊断工具，包括临床体征，心电图，生物标志物，超声心动图，MRI影像的血浆水平的评估，以及组织学分析1。急性和慢性心肌梗塞是根据相对于冠状动脉闭塞时的心肌坏死的定时列为损伤的两个不同阶段。急性期，在第7天发生，与心肌细胞的损失，广泛炎症，和成纤维细胞的招募相关联。亚急性期，其特征在于所述心脏组织和瘢痕形成的愈合，发生1和4之间 - 6周。梗死，心室壁变薄，心室扩张的扩张表征慢性期。左心室重构粗放逐步导致严重的心脏衰竭2。 MI永久左前降支（LAD）结扎引起慢性代表心肌梗死的标准啮齿动物模型。冠状动脉结扎模仿冠状动脉闭塞。梗塞的大小取决于该结扎的部位上。是用经典的生物标志物血浆水平，如肌钙蛋白执行在啮齿动物模型心肌缺血损伤的表征我和T 3，超声心动图，MRI和组织学4,5。生物标记水平与心肌死亡的程度相关。超声心动图检查评估从区域室壁运动异常导致左心功能受损。此外，非侵入性的成像技术，如MRI或高分辨率超声心动图，允许在壁运动的减少的评估，以减少灌注和存活心肌，和壁变薄的瘢痕区域的体积。 LV尺寸允许梗死面积的准确的评价。最后，可行和死心肌的量化可以用收获内心的组织切片的特殊污渍的进行尸检，并允许梗死面积（IS）的验证。另一个重要的特征是梗塞膨胀指数（EI）6的评价。在EI与内的第3天透梗死并启动有关。在EI的特征在于在壁厚的逐步减少，增加了在LV空腔尺寸，并在左心室的形状随之变化。 为了评估的新的治疗方法的治疗效果 - 尤其是，根据细胞，基质再生策略，以及在啮齿动物中的MI的基因递送精确的评估是极其重要的。当在乳头肌水平而获得的单个横截面测得，在IS大小可能由于存在于梗塞的发展以下LAD结扎的大变异被偏置;心尖梗塞可能会再遮掩。重要的是，更准确的方法来确定的梗死面积已为7-9小鼠或大鼠10所示。然而，IS不足以准确量化左室重构或重塑的治疗引起的减少（或预防措施）。事实上，IS通常表示为评估对心脏的横截面总左心室体积的百分比。虽然这种方法是有效的急性心肌梗死，重塑过程中发生的左心室壁的变薄仍在评估11,12。梗塞大小和结构变化的完整形态量化应量化的几个参数，如心内膜和心外膜的长度和直径，以及梗塞和健康领域。我们描述一个方法论APPRoach准确评估MI和重构的一种慢性大鼠模型。

<table border="0" cellpadding="0" cellspacing="0" width="775">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Acrylic rat heart matrix 2mm</td>
			<td style="width:119px;">72-5015</td>
			<td style="width:136px;">Harvard Appartus</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:247px;">INSPIRA ADVANCED VOLUME CONTROLLED VENTILATOR</td>
			<td style="width:119px;">HARVARD APPARATUS</td>
			<td style="width:136px;">557058</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">CATHETER INSYTE 14G</td>
			<td style="width:119px;">BD</td>
			<td style="width:136px;">381267</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:247px;">O.C.T</td>
			<td style="width:119px;">BDHA361603E</td>
			<td style="width:136px;">VWR</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">TTC</td>
			<td style="width:119px;">T8877-10G</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Mayer hematoxylin</td>
			<td style="width:119px;">MHS32-1L</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Acid Fuchsin 
			CI 42685</td>
			<td style="width:119px;">F8129-50G</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Ponceau Xylidin 
			CI 16150</td>
			<td style="width:119px;">P2395-25G</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Orange G 
			CI 16230</td>
			<td style="width:119px;">O3756-100G</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:247px;">Light green 
			CI 42095</td>
			<td style="width:119px;">L5382-25G</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">KCl</td>
			<td style="width:119px;">P9333-500G</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Xylol</td>
			<td style="width:119px;">10315083</td>
			<td style="width:136px;">HoneyWell</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Ethanol absolute</td>
			<td style="width:119px;">10303990</td>
			<td style="width:136px;">HoneyWell</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">2-methylbutane</td>
			<td style="width:119px;">M32631-1L</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Stereogical microscope</td>
			<td style="width:119px;">SM2800</td>
			<td style="width:136px;">Nikon</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Formaldehyde</td>
			<td style="width:119px;">99340</td>
			<td style="width:136px;">Reactolab</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Embedding cassette</td>
			<td style="width:119px;">K113.1</td>
			<td style="width:136px;">Carl Roth</td>
			<td style="width:273px;"></td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:247px;">Bersoft Image measurement Software</td>
			<td style="width:119px;"></td>
			<td style="width:136px;">Bersoft.com</td>
			<td style="width:273px;">Licensed software</td>
		</tr>
	</tbody>
</table>

histological quantification of chronic myocardial infarct in rats

Myocardial infarction is defined as cardiomyocyte death due to prolonged ischemia; an inflammatory response and scar formation (fibrosis) follow the ischemic injury. Following the initial acute phase, chronic remodeling of the left ventricle (LV) modifies the structure and function of the heart. Permanent coronary ligation in small animals has been widely used as a reference model for a chronic model of MI. Thinning of the infarcted wall progressively develops to transmural fibrosis. Histological assessment of infarct size is commonly performed; nevertheless, a standardization of the methods for quantification is missing. Indeed, important methodological aspects, such as the number of sections analyzed and the sampling and quantification methods, are usually not described and therefore preclude comparison across investigations. Too often, quantification is performed on a single section obtained at the level of the papillary muscles. Because novel strategies aimed at reducing infarct expansion and remodeling are under investigation, there is an important need for the standardization of accurate heart sampling protocols. We describe an accurate method to quantify the infarct size using a systematic sampling of harvested rat heart and image analyses of trichromatic stained histological sections obtained from base to apex. We also provide evidence that calculating the expansion index (EI) allowed for infarct size assessment, taking into account changes of the left ventricle throughout the remodeling.

六个星期后LAD结扎，心从Lewis大鼠收获。 2毫米组织切片获得从顶点基地。被执行的TTC染色过程可视化的梗塞面积，这出现在白色，与健康心肌，它出现在红（ 图2）。根据法援署结扎的部位，梗死面积变化。对于大型MI，从顶点观察到基地（ 图2A）透梗死。较小的梗塞呈现白色梗塞组织从顶点到心脏（ 图2B）的中间部分是可见的。对?...

Watch this Scientific Journal Video about Histological Quantification of Chronic Myocardial Infarct in Rats at JoVE.com

Histological Quantification of Chronic Myocardial Infarct in Rats

The post-mortem assessment of myocardial infarction (MI) in rodents is based on quantification of the infarct on stained heart sections. We describe an accurate method to quantify the infarct size using systematic sampling of harvested rat hearts from base to apex and image analyses of trichrome-stained histological sections.

大鼠慢性心肌梗塞的组织学定量分析

Myocardial infarction is defined as cardiomyocyte death due to prolonged ischemia; an inflammatory response and scar formation (fibrosis) follow the ...

histological-quantification-of-chronic-myocardial-infarct-in-rats

Research

JoVE Journal

Medicine

14.4K 次观看.  University of Fribourg. The post-mortem assessment of myocardial infarction (MI) in rodents is based on quantification of the infarct on stained heart sections. We describe an accurate method to quantify the infarct size using systematic sampling of harvested rat hearts from base to apex and image analyses of trichrome-stained histological sections. 

视频: Histological Quantification of Chronic Myocardial Infarct in Rats

Acute Myocardial Infarction in Rats

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular diseases. Animal models that mimic human cardiac disease, such as myocardial infarction (MI) and ischemia-reperfusion (IR) that induces heart failure as well as pressure-overload (transverse aortic constriction) that induces cardiac hypertrophy and heart failure (Goldman and Tarnavski), are useful models to study cardiovascular disease. In particular, myocardial ischemia (MI) is a leading cause for cardiovascular morbidity and mortality despite controlling certain risk factors such as arteriosclerosis and treatments via surgical intervention (Thygesen). Furthermore, an acute loss of the myocardium following myocardial ischemia (MI) results in increased loading conditions that induces ventricular remodeling of the infarcted border zone and the remote non-infarcted myocardium. Myocyte apoptosis, necrosis and the resultant increased hemodynamic load activate multiple biochemical intracellular signaling that initiates LV dilatation, hypertrophy, ventricular shape distortion, and collagen scar formation. This pathological remodeling and failure to normalize the increased wall stresses results in progressive dilatation, recruitment of the border zone myocardium into the scar, and eventually deterioration in myocardial contractile function (i.e. heart failure). The progression of LV dysfunction and heart failure in rats is similar to that observed in patients who sustain a large myocardial infarction, survive and subsequently develops heart failure (Goldman). The acute myocardial infarction (AMI) model in rats has been used to mimic human cardiovascular disease; specifically used to study cardiac signaling mechanisms associated with heart failure as well as to assess the contribution of therapeutic strategies for the treatment of heart failure. The method described in this report is the rat model of acute myocardial infarction (AMI). This model is also referred to as an acute ischemic cardiomyopathy or ischemia followed by reperfusion (IR); which is induced by an acute 30-minute period of ischemia by ligation of the left anterior descending artery (LAD) followed by reperfusion of the tissue by releasing the LAD ligation (Vasilyev and McConnell). This protocol will focus on assessment of the infarct size and the area-at-risk (AAR) by Evan's blue dye and triphenyl tetrazolium chloride (TTC) following 4-hours of reperfusion; additional comments toward the evaluation of cardiac function and remodeling by modifying the duration of reperfusion, is also presented. Overall, this AMI rat animal model is useful for studying the consequence of a myocardial infarction on cardiac pathophysiological and physiological function.

The rat model of acute myocardial infarction (AMI) is useful to study the consequence of a MI on cardiac pathophysiological and physiological function.

大鼠急性心肌梗死

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular ...

科研

医学

Acute and Chronic Tactile Sensory Testing after Spinal Cord Injury in Rats

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory testing in rat SCI models is needed. However, until recently, no single testing approach had been validated for SCI so that standardized methods have not been implemented across labs. Additionally, available testing methods could not be implemented acutely or when severe motor impairments existed, preventing studies of the development of SCI-induced allodynia3. Here we present two validated sensory testing methods using von Frey Hair (VFH) monofilaments which quantify changes in tactile sensory thresholds after SCI4-5. One test is the well-established Up-Down test which demonstrates high sensitivity and specificity across different SCI severities when tested chronically5. The other test is a newly-developed dorsal VFH test that can be applied acutely after SCI when allodynia develops, prior to motor recovery4-5. Each VFH monofilament applies a calibrated force when touched to the skin of the hind paw until it bends. In the up-down method, alternating VFHs of higher or lower forces are used on the plantar L5 dermatome to delineate flexor withdrawal thresholds. Successively higher forces are applied until withdrawal occurs then lower force VFHs are used until withdrawal ceases. The tactile threshold reflects the force required to elicit withdrawal in 50% of the stimuli. For the new test, each VFH is applied to the dorsal L5 dermatome of the paw while the rat is supported by the examiner. The VFH stimulation occurs in ascending order of force until at least 2 of 3 applications at a given force produces paw withdrawal. Tactile sensory threshold is the lowest force to elicit withdrawal 66% of the time. Acclimation, testing and scoring procedures are described. Aberrant trials that require a retest and typical trials are defined. Animal use was approved by Ohio State University Animal Care and Use Committee.

We describe two tactile sensory testing methods for acute or chronic periods of spinal cord injury in rats. These validated procedures can detect the development and maintenance of allodynia-like sensations.

在大鼠脊髓损伤后的急性和慢性触觉测试

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory ...

Chronic Constriction of the Sciatic Nerve and Pain Hypersensitivity Testing in Rats

Chronic neuropathic pain, resulting from damage to the central or peripheral nervous system, is a prevalent and debilitating condition, affecting 7-18% of the population1,2. Symptoms include spontaneous (tingling, burning, electric-shock like) pain, dysaesthesia, paraesthesia, allodynia (pain resulting from normally non-painful stimuli) and hyperalgesia (an increased response to painful stimuli). The sensory symptoms are co-morbid with behavioural disabilities, such as insomnia and depression. To study chronic neuropathic pain several animal models mimicking peripheral nerve injury have been developed, one of the most widely used is Bennett and Xie's (1988) unilateral sciatic nerve chronic constriction injury (CCI)3 (Figure 1). Here we present a method for performing CCI and testing pain hypersensitivity.
CCI is performed under anaesthesia, with the sciatic nerve on one side exposed by making a skin incision, and cutting through the connective tissue between the gluteus superficialis and biceps femoris muscles. Four chromic gut ligatures are tied loosely around the sciatic nerve at 1 mm intervals, to just occlude but not arrest epineural blood flow. The wound is closed with sutures in the muscle and staples in the skin. The animal is then allowed to recover from surgery for 24 hrs before pain hypersensitivity testing begins.
For behavioural testing, rats are placed into the testing apparatus and are allowed to habituate to the testing procedure. The area tested is the mid-plantar surface of the hindpaw (Figure 2), which falls within the sciatic nerve distribution. Mechanical withdrawal threshold is assessed by mechanically stimulating both injured and uninjured hindpaws using an electronic dynamic plantar von Frey aesthesiometer or manual von Frey hairs4. The mechanical withdrawal threshold is the maximum pressure exerted (in grams) that triggers paw withdrawal. For measurement of thermal withdrawal latency, first described by Hargreaves et al (1988), the hindpaw is exposed to a beam of radiant heat through a transparent glass surface using a plantar analgesia meter5,6. The withdrawal latency to the heat stimulus is recorded as the time for paw withdrawal in both injured and uninjured hindpaws. Following CCI, mechanical withdrawal threshold, as well as thermal withdrawal latency in the injured paw are both significantly reduced, compared to baseline measurements and the uninjured paw (Figure 3). The CCI model of peripheral nerve injury combined with pain hypersensitivity testing provides a model system to investigate the effectiveness of potential therapeutic agents to modify chronic neuropathic pain. In our laboratory, we utilise CCI alongside thermal and mechanical sensitivity of the hindpaws to investigate the role of neuro-immune interactions in the pathogenesis and treatment of neuropathic pain.

Due to the simplicity of surgery and the robust behavioural outcome, chronic constriction of the sciatic nerve is one of the pre-eminent animal models of neuropathic pain. Within 24 hrs following surgery, pain hypersensitivity is established and can be quantitatively measured using a von Frey aesthesiometer (mechanical test) and plantar analgesia meter (thermal test).

慢性缩窄大鼠坐骨神经疼痛过敏测试

Chronic neuropathic pain, resulting from damage to the central or peripheral nervous system, is a prevalent and debilitating condition, affecting 7-18% of ...

Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery (SALLI) MRI in Rats

Small animal magnetic resonance imaging is an important tool to study cardiac function and changes in myocardial tissue. The high heart rates of small animals (200 to 600 beats/min) have previously limited the role of CMR imaging. Small animal Look-Locker inversion recovery (SALLI) is a T1 mapping sequence for small animals to overcome this problem 1. T1 maps provide quantitative information about tissue alterations and contrast agent kinetics. It is also possible to detect diffuse myocardial processes such as interstitial fibrosis or edema 1-6. Furthermore, from a single set of image data, it is possible to examine heart function and myocardial scarring by generating cine and inversion recovery-prepared late gadolinium enhancement-type MR images 1.
	The presented video shows step-by-step the procedures to perform small animal CMR imaging. Here it is presented with a healthy Sprague-Dawley rat, however naturally it can be extended to different cardiac small animal models.

Assessment of Cardiac Function and Myocardial Morphology Using Small Animal Look-locker Inversion Recovery SALLI MRI in Rats

Contrast enhanced cardiac magnetic resonance (CMR) imaging allows comprehensive in vivo assessment of the heart in small animal models of cardiovascular disease. Here we detail the procedures to perform CMR imaging, reconstruction and analysis using Small Animal Lock-Locker Inversion Recovery (SALLI) in rats.

使用小动物看更衣室反转恢复（SALLI）的MRI大鼠心脏功能和心肌形态学评估

Small animal magnetic resonance  imaging is an important tool to study cardiac function and changes in myocardial  tissue. The high heart rates of small ...

MRI and PET in Mouse Models of Myocardial Infarction

Myocardial infarction is one of the leading causes of death in the Western world. The similarity of the mouse heart to the human heart has made it an ideal model for testing novel therapeutic strategies.
In vivo magnetic resonance imaging (MRI) gives excellent views of the heart noninvasively with clear anatomical detail, which can be used for accurate functional assessment. Contrast agents can provide basic measures of tissue viability but these are nonspecific. Positron emission tomography (PET) is a complementary technique that is highly specific for molecular imaging, but lacks the anatomical detail of MRI. Used together, these techniques offer a sensitive, specific and quantitative tool for the assessment of the heart in disease and recovery following treatment.
In this paper we explain how these methods are carried out in mouse models of acute myocardial infarction. The procedures described here were designed for the assessment of putative protective drug treatments. We used MRI to measure systolic function and infarct size with late gadolinium enhancement, and PET with fluorodeoxyglucose (FDG) to assess metabolic function in the infarcted region. The paper focuses on practical aspects such as slice planning, accurate gating, drug delivery, segmentation of images, and multimodal coregistration. The methods presented here achieve good repeatability and accuracy maintaining a high throughput.

We describe how to perform MRI and PET imaging of the mouse heart. The protocol is tailored to assess treatment efficacy in models of myocardial infarction and heart failure.

MRI和PET心肌梗死小鼠模型

Myocardial infarction is one of the leading causes of death in the Western world. The similarity of the mouse heart to the human heart has made it an ...

Ultrasonic Assessment of Myocardial Microstructure

Echocardiography is a widely accessible imaging modality that is commonly used to noninvasively characterize and quantify changes in cardiac structure and function. Ultrasonic assessments of cardiac tissue can include analyses of backscatter signal intensity within a given region of interest. Previously established techniques have relied predominantly on the integrated or mean value of backscatter signal intensities, which may be susceptible to variability from aliased data from low frame rates and time delays for algorithms based on cyclic variation. Herein, we describe an ultrasound-based imaging algorithm that extends from previous methods, can be applied to a single image frame&#160;and accounts for the full distribution of signal intensity values derived from a given myocardial sample. When applied to representative mouse and human imaging data, the algorithm distinguishes between subjects with and without exposure to chronic afterload resistance. The algorithm offers an enhanced surrogate measure of myocardial microstructure and can be performed using open-access image analysis software.

Echocardiography is commonly used to noninvasively characterize and quantify changes in cardiac structure and function. We describe an ultrasound-based imaging algorithm that offers an enhanced surrogate measure of myocardial microstructure and can be performed using open-access image analysis software.

心肌微观结构超声波评估

Echocardiography is a widely accessible imaging modality that is commonly used to noninvasively characterize and quantify changes in cardiac structure and ...

Urinary Bladder Distention Evoked Visceromotor Responses as a Model for Bladder Pain in Mice

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition characterized by increased urgency and frequency of urination, as well as nocturia and general pelvic pain, especially upon bladder filling or voiding. Despite years of research, the cause of IC/BPS remains elusive and treatment strategies are unable to provide complete relief to patients. In order to study nervous system contributions to the condition, many animal models have been developed to mimic the pain and symptoms associated with IC/BPS. One such murine model is urinary bladder distension (UBD). In this model, compressed air of a specific pressure is delivered to the bladder of a lightly anesthetized animal over a set period of time. Throughout the procedure, wires in the superior oblique abdominal muscles record electrical activity from the muscle. This activity is known as the visceromotor response (VMR) and is a reliable and reproducible measure of nociception. Here, we describe the steps necessary to perform this technique in mice including surgical manipulations, physiological recording, and data analysis. With the use of this model, the coordination between primary sensory neurons, spinal cord secondary afferents, and higher central nervous system areas involved in bladder pain can be unraveled. This basic science knowledge can then be clinically translated to treat patients suffering from IC/BPS.

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition characterized in part by pelvic pain. In order to study nervous system contributions to the condition, a physiological model of urinary bladder pain is used in mice and rats.

膀胱胀诱发内脏运动反应为膀胱疼痛小鼠模型

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition ...

Echocardiographic and Histological Examination of Cardiac Morphology in the Mouse

An increasing number of genetically modified mouse models has become available in recent years. Moreover, the number of pharmacological studies performed in mice is high. Phenotypic characterization of these mouse models also requires the examination of cardiac function and morphology. Echocardiography and magnetic resonance imaging (MRI) are commonly used approaches to characterize cardiac function and morphology in mice. Echocardiographic and MRI equipment specialized for use in small rodents is&#160;expensive and requires a dedicated space. This protocol describes cardiac measurements in mice using a clinical echocardiographic system with a 15 MHz human vascular probe. Measurements are performed on anesthetized adult mice. At least three image sequences are recorded and analyzed for each animal in M-mode in the parasternal short-axis view. Afterwards, cardiac histological examination is performed, and cardiomyocyte diameters are determined on hematoxylin-eosin- or wheat germ agglutinin (WGA)-stained paraffin sections. Vessel density is determined morphometrically after Pecam-1 immunostaining. The protocol has been applied successfully to pharmacological studies and different genetic animal models under baseline conditions, as well as after experimental myocardial infarction by the permanent ligation of the left anterior descending coronary artery (LAD). In our experience, echocardiographic investigation is limited to anesthetized animals and is feasible in adult mice weighing at least 25 g.

Echocardiographic examination is frequently used in mice. Expensive high-resolution ultrasound devices have been developed for this purpose. This protocol describes an affordable echocardiographic procedure combined with histological morphometric analyses to determine cardiac morphology.

超声心动图与小鼠心脏形态学的组织学检查

An increasing number of genetically modified mouse models has become available in recent years. Moreover, the number of pharmacological studies performed ...

Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via recanalization of the coronary artery is the most effective strategy for reducing the size of ischemic myocardium. The coronary microvasculature cannot be visualized and imaged&#160;in vivo, but there are several invasive and noninvasive techniques that can be used to assess parameters which depend directly on coronary microvascular function. The endothelial function after ischemia reperfusion can be assessed also at the level of the coronary circulation via the coronary flow reserve (CFR).&#160;In this study, peak velocity of left anterior descending (LAD) coronary arteries was measured in rats in vivo via Transthoracic Doppler Echocardiography during resting and stress challenge (induced by Dobutamine). A normal heart can increase its coronary blood flow up to four times above the resting values during stress induction. Following ischemia reperfusion, we found a significantly diminished CFR, which can be used as a marker of coronary microvascular dysfunction. CFR has opened a window on the importance of microvascular dysfunction and has been shown to predict cardiovascular risk independent of whether the severe obstructive disease is present.

Coronary flow reserve (CFR), is defined as the ratio of maximal coronary blood flow to the resting coronary blood flow. We present a protocol for evaluating CFR in rats via ultrasound, which offers the opportunity to predict cardiovascular risk factors in the absence of obstructive coronary disease.

大鼠心肌缺血再灌注后冠状动脉流动储备评价

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via ...

Semi-Minimal Invasive Method to Induce Myocardial Infarction in Rats and the Assessment of Cardiac Function by an Isolated Working Heart System

Myocardial infarction (MI) remains the main contributor to morbidity and mortality worldwide. Therefore, research on this topic is mandatory. An easily and highly reproducible MI induction procedure is required to obtain further insight and better understanding of the underlying pathological changes. This procedure can also be used to evaluate the effects or potency of new and promising treatments (as drugs or interventions) in acute MI, subsequent remodeling and heart failure (HF). After intubation and pre-operative preparation of the animal, an anesthetic protocol with isoflurane was performed, and the surgical procedure was conducted&#160;quickly. Using a minimally invasive approach, the left anterior descending artery (LAD) was located and occluded by a ligature. The occlusion can be performed acutely for subsequent reperfusion (ischemia/reperfusion injury). Alternatively, the vessel can be ligated permanently to investigate the development of chronic MI, remodeling or HF. Despite common pitfalls, the drop-out rates are minimal. Various treatments such as remote ischemic conditioning can be examined for their cardioprotective potential pre-, peri- and post-operatively. The post-operative recovery was quick as the anesthesia was precisely controlled and the duration of the operation was short. Post-operative analgesia was administered for three days. The minimally invasive procedure reduces the risk of infection and inflammation. Furthermore, it facilitates rapid recovery. The &#8220;working heart&#8221; measurements were performed ex vivo and enabled precise control of preload, afterload and flow. This procedure requires specific equipment and training for adequate performance. This manuscript provides a detailed step-by-step introduction for conducting these measurements.

This article presents an efficient method to perform myocardial ischemia and subsequent chronic reperfusion in rats using a minimally invasive approach. In addition, left ventricular hemodynamic function of rats is assessed by echocardiography and isolated working heart methods.&#160;

诱导大鼠心肌梗死的半微创方法及独立工作心脏系统对心脏功能的评估

Myocardial infarction (MI) remains the main contributor to morbidity and mortality worldwide. Therefore, research on this topic is mandatory. An easily ...