目前的研究是支持由美国国家心脏，肺和血液研究所资助以R01 - HL0921，R01 - DK083385和R01 - HL098294港元Eltzschig，1K08HL102267 - 01 T。Eckle，并到T麻醉教育和科研资助基金会Eckle和香港Eltzschig，美国心脏协会授予T. Eckle和香港Eltzschig和德意志研究联合会（DFG）的研究奖学金M. KOEPPEN。我们感谢雪莱Eltzschig艺术作品。

总论: 所有操作应下一个堂堂正正的解剖显微镜（奥林巴斯，与Z轴与STU2 StandBoom支架曲柄邮政SZX10）和使用手术凝固剂。通风是程序的关键，因此，应选择呼吸机和优化的通风技术花一定的时间。体温，血压和麻醉应稳定。 1。麻醉，气管插管和监测<ol><li>使用C57BL / 6小鼠至少10周龄。使用的剂量70毫克/公斤体重IP戊巴比妥钠诱导麻醉维持约10毫克/公斤/小时戊巴比妥钠麻醉。小心过量，因为这可能会显着降低血压。给药苯巴比妥 - 即使小时，可导致血浆中的严重增加。基于有力的证据，如心脏复合异氟醚，我们建议使用"惰性"，并在心肌缺血46-56模型以及建立巴比妥。 </li><li>广场小鼠加热温度控制表（RT，埃芬博格，慕尼黑，德国）与直肠温度计探头连接到热反馈控制器，以保持体温在37 ° C。 </li><li>麻醉诱导后，在仰卧位表使用磁带和一期缝合固定脚踝上，下肢，安全小鼠。不要使用牙齿相同的头部。一个足够的限制是很重要的一个成功的插管，并得到很好的控制手术。手术前，盖与矿物油鼠标，以减少鼠毛过敏的风险。 </li><li>气管外科手术暴露和使用bluntpolyethylene套管（Insyte 22G，Beckton Dickinson公司，美国）进行气管插管。您将有钝针，可以使用它作为一个钢丝。 </li><li>使用一双镊子拉出舌头，然后轻轻推在一个15度角朝向身体。即使在暴露气管，用显微镜，这可能需要一些训练。要知道，一个小的损伤气管，可能导致无法通风的动物，在整个缝合。因此，如果你遇到呼吸道问题，检查气管小孔。 </li><li>通过导管直接可视化确认正确的管放置在以前暴露气管隆突以上。 </li><li>呼吸机连接管。我们建议使用由西门子 （DRE兽医，美国）伺服900℃，压力控制通气技术。然后将动物使用一个FIO 2 = 0.4，吸气峰压10毫巴，频率为110次/分和3-5 mbar的压力呼气末正压通风。设置可能需要一些可以打开胸腔手术中通过检查肺部最容易实现的调整。确保肺部都没有倒塌或过度。尽管伺服900℃是人类呼吸机内置的事实，其压力控制呼吸机设置使用作品的优秀小鼠的通风。 </li><li>执行后4至6小时的通风时间，使用I - STAT血气分析，以确认正常的气体交换（氧分压，PAO 2 115 ± 15毫米汞柱氧分压和二氧化碳，PACO 38 2 ± 6毫米汞柱）系统（雅培公司，美国）。 </li><li>监控心率与心电图（如惠普，Böblingen的，德国）。确保心率不低于450。如果鼠标的发展bradicardia检查温度和麻醉剂的剂量/浓度。 Xylacin /氯胺酮麻醉诱导烂熟于心了250元/分钟，因此不推荐。 </li><li>应用适当的补液。一个输液生理盐水0.1毫升/小时通过动脉或静脉导管应缺血发作之前执行。另外，500μL生理盐水静脉推注可给予手术前的IP。 Thoractomy可诱发血压下降，可能需要额外的生理盐水玻璃。缺血后，输液速度高达1毫升/小时，可能是要保持60毫米汞柱以上，平均动脉血压，以保证有足够的再灌注心肌梗死使用TTC染色的关键。 </li><li>放置一个连续记录血压的颈动脉（PE10，提示外径（毫米/"），圆锥&gt; 0.024 mm/.011"）。颈内动脉，将通过钝性分离气管肌肉暴露。经过进一步的接触和小心避免任何组织创伤（尤其是迷走神经），导管插入使用两个缝线和一个小钳的船只。将手臂向身体，然后再开始解剖动脉。这将会使一块较长的动脉。结的颈动脉近端部分的结束。将较大的钳缝合结束获得紧张。将另一个周围动脉缝合动脉解剖的末端。在这里，放在一个小卡子。使用微型剪刀剪一小对角线开放到动脉。与罚款钳（杜蒙，WPI），保持开放和推进适当大小的导管，用你的手/钳。您的第二缝合打了一个结，安全的动脉。松开夹子，并进一步推进导管。安全与几节和磁带的导管。 </li></ol> 2。冠状动脉闭塞技术<ol><li>剖析皮肤暴露左侧胸腔壁使用钝性分离技术。 </li><li>剪下的肌肉胸肌专业和未成年人的揭露与胸腔壁烧灼。拉胸大肌，肺下降，从而钳电刀单元从一个可插入，并1-3毫米以上的肺癌，水平线跨越的裂口，应凝固。 </li><li>通过使用钝剪刀，剪开胸腔壁。然后用修改安全别针，赶上板被删除，钝年底弯曲，保持胸部打开。 </li><li>为了便于最后的缝合位置，凝聚和削减沿着隔膜对胸廓的左侧胸腔壁。 </li><li>暴露心脏解剖心包。为了避免膈肌运动中删除，并切断膈神经。 </li><li>一个钳使用一个小型的湿棉签，转向右侧的心。确定左冠状动脉（LCA）和确保肺部不是太夸大。优化开放胸廓配售缝合时，有一种心灵的安全举行。如果血压太低可能是复杂的鉴定。生理盐水的玻璃可能提高识别的LCA。 LCA是一个鲜红的一艘过路的心脏水平（对比选举静脉）。有时，LCA是没有显微镜的最佳。不要使用太多的光。这可能会导致可视化不可能割断反射。 </li><li>一旦LCA是视觉识别，围绕LCA 8.0尼龙缝线（普理灵，美国，Notiefies，爱惜康）。对于间歇性LCA闭塞的目的，我们通过使用吊重系统的慢性心肌病 42的模型。 </li><li>穿过钝边的小块的塑料管（PE - 10管）的缝合，每年年底将两个小重量（1G，如使用的Eppendorf管装满水）。 LCA的自由挂杆的重量，应立即闭塞。此外，当重量减轻，生命周期闭塞是一次终止。成功的LCA的闭塞，应确认由船只从淡红色到暗紫色，心肌的颜色变化，船只（从鲜艳的红色为白色）和在心电图ST -海拔的存在提供了直接的颜色变化。在灌注过程中，颜色的变化，瞬间消失。保持心脏与37℃，盐水浸泡，一块脱脂棉整个（参见图1）湿。 </li><li>选择最适合你的缺血时间根据你的主要兴趣。事实上，IP的心脏保护作用的研究，它将是理想的使用与梗塞大小约30％至40％在AAR，缺血时间。因此，将有可能证明在两个方向上的变化，如心脏的实验治疗或特定基因缺失的IP或较大梗塞大小尺寸较小梗死。此外，低于50％的心肌梗死面积的小鼠生存实验，而60％至80％的心肌梗死大小往往不能成活和动物死亡前，再灌注时间完成。使用我们的模型中，心肌缺血10分钟2小时再灌注结果梗死面积3.5 ± 1.3％在AAR。与此相反，缺血时间60分钟结果，平均梗死面积在42 ± 5.2％，在AAR（P &lt;0.01） 39。因此，我们认为，缺血60分钟为理想，以研究在两个方向上的变化。然而，你可能需要调整断绝表型与基因小鼠缺血时间。 </li><li>选择了正确的再灌注时间。 TTC染色再灌注时间是非常重要的。无色染料是由脱氢酶在辅酶NADH的存在降低到一个砖红色沉淀。死亡的细胞失去了自己的能力，保留NADH和，因此，内红染色存活心肌苍白地区划定。梗死TTC大小划定需要，NADH的已冲了出去，完全坏死区。但是，如果再灌注不够长，TTC染色梗死面积的划分可能导致低估实际的梗死面积43。在我们手中，缺血时间60分钟后，梗死面积测量增加11.5 ± 4.5％，30分钟后，以42.2 ± 5.1％经过120分钟。无梗死面积进一步增加，可检测与再灌注时间较长（240分钟）39。因此，我们建议2小时再灌注期，这似乎也是在你考虑缺血预处理的心脏酶determination.If的范围内合理的，我们推荐了4个周期的IP（5分钟缺血，再灌注5分钟），缺血时间60 min和再灌注时间为2小时。在这些情况下，IP与梗死面积的3.2倍减少，从42.2 ± 5.1％至13.3 ± 3.3％ 的 AAR 39。然而，由于吊重系统，不同的预处理团，可以很容易地被应用。 </li></ol> 3。测定该地区的风险（AAR）和心肌梗死面积诱导心肌梗死（带或不带IP）"后，该地区是由LCA（在危险区，AAR）和梗死面积，使用染色技术本身将决定灌注。随后，心肌梗死，然后计算出心肌梗死的百分比相比，在AAR。要做到这一点，先前所描述的埃文的蓝色和三苯基氯化四氮唑（TTC）双重染色技术是使用44。 <ol><li> LCA是闭塞而确定的1％埃文的蓝色染料进入主动脉逆行注射在AAR。另外，如果颈动脉导管到位，使用这条线路为伊文思蓝注射液。伊文思蓝染色所有心肌组织蓝色，在AAR除外。这一步是关键，以避免导管内的气泡，因为他们将注入冠脉循环和防止埃文的蓝染色。伊文思蓝染色之前，你可能想收集测量心脏酶的血液。此外，建议去除血液通过主动脉或颈动脉导管注入5毫升生理盐水。 </li><li>海关的心，在冰冷的0.9％生理盐水洗</li><li>嵌入到2％琼脂糖。不要用太热的琼脂糖凝胶，因为这将阻止成功染色。 </li><li>经过30分钟+4 ° C（或15分钟-20℃），切到1毫米，使用心脏矩阵或切片机切片的核心。如果你放入冷冻心脏，避免干燥冻结，这将导致非染色的心中。 </li><li>孵育切片，用1％TTC在37 ° C为10分钟水浴中使用了15毫升的蓝帽。这将允许梗死面积为白色区域划分，红色污渍而可行的组织。 </li><li>注视与10％以上夜间fomaldehyde的染色切片。通过这样做，是更好地对比梗死面积，改善图像质量。 </li><li>确定危险区（AAR）和梗死面积通过使用美国国立卫生研究院的软件映像1.0 45 planimetry。 </li><li>计算％心肌梗死的风险领域。 </li></ol> 4。心脏酶测量由于与TTC染色相关的限制，我们建议增加心肌梗死的严重程度测定心脏肌钙蛋白I（cTnI）水平在小鼠血清的读数。血液将获得来自门静脉和血清cTnI水平，然后确定一个量化的快速cTnI检测（诊断西切斯特宾夕法尼亚，美国）。 5。代表性的成果: <img src="/files/ftp_upload/2526/2526fig1.jpg" alt="图1" /> 图1:（一）心脏知识产权的型号，使用吊重系统的冠状动脉闭塞。这种技术并不需要为冠状动脉闭塞的结。 （B，C）手术的设置。 （四）图像与小鼠左冠状动脉心脏病后的阻塞（LCA，箭头）。 LCA的视觉识别结扎和小鼠缺血预处理是必要的。 8.0尼龙缝线置于下方的左耳廓周围LCA 1-2毫米。缝线穿过一个小塑料管（*）连接到每个缝合结束一个小，重量轻（1G）和缝合过棒放在两侧。 （五）在AAR LCA的闭塞和埃文蓝色染料进入主动脉逆行注射后测定。在AAR仍然不染，而其余的心肌是蓝色。后是AAR与TTC组织，梗死面积沾上白色的孵化，而可行的组织染成红色。

本研究描述了一个执行一个完整的小鼠模型，使用吊重系统的IP，从而避免了一个结冠状动脉阻塞的新技术。事实上，这项研究表明，通过IP的高度重复性的梗塞大小和心脏保护作用，从而减少结冠状动脉闭塞模型的可变性。考虑研究的小鼠心肌保护知识产权的调查可能会受益于这种模式。

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<td>Sodium Pentobarbital (Fatal Plus)</td>
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use of a hanging weight system for coronary artery occlusion in mice

小鼠急性损伤的研究是一个地区的紧张调查，为不同的基因敲除小鼠也日趋，可用1-38。心肌缺血预处理（IP）的面积仍然紧张调查。为了进一步阐明其分子基础，利用基因敲除小鼠研究显得尤为重要7，14，30，39。尽管以往的研究已经成功地执行在小鼠心肌缺血再灌注，这种模式在技术上是非常具有挑战性。特别是视觉识别安置缝合打结与支持结船只周围的血管和冠状动脉闭塞的冠状动脉，技术上是困难的。此外，重新开放结间歇性的冠状动脉再灌注过程中的IP不会造成手术创伤，增加了额外的挑战。此外，如果结不下来并列足够强大，无心再灌注由于不完善闭塞的冠状动脉，可能会影响结果。事实上，这可以很容易出现由于跳动的心脏运动。 使用打结的冠状动脉闭塞系统相关的潜在问题的基础上，我们通过察看的慢性心肌病模型的基础上间歇性冠状动脉闭塞的挂减肥期间的IP 39系统。事实上，冠状动脉阻塞从而可以实现，而无需一个结闭塞的冠状动脉。此外，再灌注的船只可以轻松实现，支持在心脏组织的远程本地化的悬挂重量。 我们测试系统，这个系统包括缺血再灌注时，预处理团，体温和39个遗传背景的变化。此外梗死染色，我们测试了一个标记，在这个模型的心肌梗死心肌肌钙蛋白I（cTnI）。事实上，cTnI的血浆水平与梗塞大小（R2 = 0.8）。最后，我们可以在几项研究显示，这种技术产生，在小鼠的IP和心肌梗死6，8，30，40，41的高度重复性的梗塞大小。因此，这项技术可能有助于研究人员追求IP使用一种遗传性的方法有针对性的基因缺失的小​​鼠心肌涉及的分子机制。对心脏的IP进一步研究，利用转基因小鼠可考虑这项技术。

Watch this Scientific Journal Video about Use of a Hanging Weight System for Coronary Artery Occlusion in Mice at JoVE.com

Use of a Hanging Weight System for Coronary Artery Occlusion in Mice

一个小鼠心肌缺血及缺血预处理模型的一个重要手段心脏保护机制研究<em&gt;在体内</em&gt;。在这里，我们报告一件容易的适用<em&gt;原位</em&gt;车型心脏冠状动脉阻塞使用一个吊重系统的IP。

悬重系统的使用在小鼠冠状动脉闭塞

Murine studies of acute injury are an area of intense investigation, as knockout mice for different genes are becoming increasingly available 1-38. ...

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21.5K 次观看.  University of Colorado Denver. 一个小鼠心肌缺血及缺血预处理模型的一个重要手段心脏保护机制研究在体内。在这里，我们报告一件容易的适用原位车型心脏冠状动脉阻塞使用一个吊重系统的IP。

视频: Use of a Hanging Weight System for Coronary Artery Occlusion in Mice

Modeling Stroke in Mice - Middle Cerebral Artery Occlusion with the Filament Model

Stroke is among the most frequent causes of death and adult disability, especially in highly developed countries. However, treatment options to date are very limited. To meet the need for novel therapeutic approaches, experimental stroke research frequently employs rodent models of focal cerebral ischaemia. Most researchers use permanent or transient occlusion of the middle cerebral artery (MCA) in mice or rats.
Proximal occlusion of the middle cerebral artery (MCA) via the intraluminal suture technique (so called filament or suture model) is probably the most frequently used model in experimental stroke research. The intraluminal MCAO model offers the advantage of inducing reproducible transient or permanent ischaemia of the MCA territory in a relatively non-invasive manner. Intraluminal approaches interrupt the blood flow of the entire territory of this artery. Filament occlusion thus arrests flow proximal to the lenticulo-striate arteries, which supply the basal ganglia. Filament occlusion of the MCA results in reproducible lesions in the cortex and striatum and can be either permanent or transient. In contrast, models inducing distal (to the branching of the lenticulo-striate arteries) MCA occlusion typically spare the striatum and primarily involve the neocortex. In addition these models do require craniectomy. In the model demonstrated in this article, a silicon coated filament is introduced into the common carotid artery and advanced along the internal carotid artery into the Circle of Willis, where it blocks the origin of the middle cerebral artery. In patients, occlusions of the middle cerebral artery are among the most common causes of ischaemic stroke. Since varying ischemic intervals can be chosen freely in this model depending on the time point of reperfusion, ischaemic lesions with varying degrees of severity can be produced. Reperfusion by removal of the occluding filament at least partially models the restoration of blood flow after spontaneous or therapeutic (tPA) lysis of a thromboembolic clot in humans.
In this video we will present the basic technique as well as the major pitfalls and confounders which may limit the predictive value of this model.

Filamentous occlusion of the Middle cerebral artery is a common model for studying ischemic stroke in mice.

建模在小鼠体内的行程 - 中东与灯丝模型大脑中动脉闭塞

Stroke is among the most frequent causes of death and adult disability, especially in highly developed countries. However, treatment options to date are ...

科研

医学

Use of a Hanging-weight System for Isolated Renal Artery Occlusion

In hospitalized patients, over 50% of cases of acute kidney injury (AKI) are caused by renal ischemia 1-3. A recent study of hospitalized patients revealed that only a mild increase in serum creatinine levels (0.3 to 0.4 mg/dl) is associated with a 70% greater risk of death than in persons without any increase 1. Along these lines, surgical procedures requiring cross-clamping of the aorta and renal vessels are associated with a renal failure rates of up to 30% 4. Similarly, AKI after cardiac surgery occurs in over 10% of patients under normal circumstances and is associated with dramatic increases in mortality. AKI are also common complications after liver transplantation. At least 8-17% of patients end up requiring renal replacement therapy 5. Moreover, delayed graft function due to tubule cell injury during kidney transplantation is frequently related to ischemia-associated AKI 6. Moreover, AKI occurs in approximately 20% of patients suffering from sepsis 6.The occurrence of AKI is associated with dramatic increases of morbidity and mortality 1. Therapeutic approaches are very limited and the majority of interventional trials in AKI have failed in humans. Therefore, additional therapeutic modalities to prevent renal injury from ischemia are urgently needed 3, 7-9. 
To elucidate mechanisms of renal injury due to ischemia and possible therapeutic strategies murine models are intensively required 7-13. Mouse models provide the possibility of utilizing different genetic models including gene-targeted mice and tissue specific gene-targeted mice (cre-flox system). However, murine renal ischemia is technically challenging and experimental details significantly influence results. We performed a systematic evaluation of a novel model for isolated renal artery occlusion in mice, which specifically avoids the use of clamping or suturing the renal pedicle 14. This model requires a nephrectomy of the right kidney since ischemia can be only performed in one kidney due to the experimental setting. In fact, by using a hanging-weight system, the renal artery is only instrumented once throughout the surgical procedure. In addition, no venous or urethral obstruction occurs with this technique. We could demonstrate time-dose-dependent and highly reproducible renal injury with ischemia by measuring serum creatinine. Moreover, when comparing this new model with conventional clamping of the whole pedicle, renal protection by ischemic preconditioning is more profound and more reliable. Therefore his new technique might be useful for other researchers who are working in the field of acute kidney injury.

A precise murine model for acute kidney injury (AKI) due to ischemia is an important tool to investigate acute kidney injury and possibly find therapeutic tools to treat renal injury. The hanging weight system offers a tool for immediate and reliable renal artery occlusion and reperfusion without causing renal congestion.

一个悬重系统使用隔离肾动脉闭塞

In hospitalized patients, over 50% of cases of acute kidney injury (AKI) are caused by renal ischemia 1-3. A recent study of hospitalized patients ...

Use of a Hanging-weight System for Liver Ischemia in Mice

Acute liver injury due to ischemia can occur during several clinical procedures e.g. liver transplantation, hepatic tumor resection or trauma repair and can result in liver failure which has a high mortality rate1-2. Therefore murine studies of hepatic ischemia have become an important field of research by providing the opportunity to utilize pharmacological and genetic studies3-9. Specifically, conditional mice with tissue specific deletion of a gene (cre, flox system) provide insights into the role of proteins in particular tissues10-13 . Because of the technical difficulty associated with manually clamping the portal triad in mice, we performed a systematic evaluation using a hanging-weight system for portal triad occlusion which has been previously described3. By using a hanging-weight system we place a suture around the left branch of the portal triad without causing any damage to the hepatic lobes, since also the finest clamps available can cause hepatic tissue damage because of the close location of liver tissue to the vessels. Furthermore, the right branch of the hepatic triad is still perfused thus no intestinal congestion occurs with this technique as blood flow to the right hepatic lobes is preserved. Furthermore, the portal triad is only manipulated once throughout the entire surgical procedure. As a result, procedures like pre-conditioning, with short times of ischemia and reperfusion, can be easily performed. Systematic evaluation of this model by performing different ischemia and reperfusion times revealed a close correlation of hepatic ischemia time with liver damage as measured by alanine (ALT) and aspartate (AST) aminotransferase serum levels3,9. Taken together, these studies confirm highly reproducible liver injury when using the hanging-weight system for hepatic ischemia and intermittent reperfusion. Thus, this technique might be useful for other investigators interested in liver ischemia studies in mice. Therefore the video clip provides a detailed step-by-step description of this technique.

We established a novel murine model of a hanging weight system for portal triad occlusion. This technique may be useful for future investigations of ischemia in murine hepatic models.

使用吊重系统在小鼠肝缺血

Acute liver injury due to ischemia can occur during several clinical procedures e.g. liver transplantation, hepatic tumor resection or trauma repair and ...

Modified Technique for Coronary Artery Ligation in Mice

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI we need better knowledge about pathophysiology of myocardial ischemia. This knowledge may be valuable to define new therapeutic targets for innovative cardiovascular therapies4. Experimental MI model in mice is an increasingly popular small-animal model in preclinical research in which MI is induced by means of permanent or temporary ligation of left coronary artery (LCA)5. In this video, we describe the step-by-step method of how to induce experimental MI in mice.
The animal is first anesthetized with 2% isoflurane. The unconscious mouse is then intubated and connected to a ventilator for artificial ventilation. The left chest is shaved and 1.5 cm incision along mid-axillary line is made in the skin. The left pectoralis major muscle is bluntly dissociated until the ribs are exposed. The muscle layers are pulled aside and fixed with an eyelid-retractor. After these preparations, left thoracotomy is performed between the third and fourth ribs in order to visualize the anterior surface of the heart and left lung. The proximal segment of LCA artery is then ligated with a 7-0 ethilon suture which typically induces an infarct size ~40% of left ventricle. At the end, the chest is closed and the animals receive postoperative analgesia (Temgesic, 0.3 mg/50 ml, ip). The animals are kept in a warm cage until spontaneous recovery.

The surgical procedure used to induce experimental myocardial infarction in mice begins with left thoracotomy between the third and the fourth ribs in order to visualize the anterior surface of the heart and left lung. The left coronary artery is ligated, the chest is closed and the mouse is allowed to recover spontaneously.

改性技术在小鼠冠状动脉结扎

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI ...

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

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

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

颈动脉输液的紫杉烷类化合物在小鼠体内的药代动力学和药效学分析

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

Permanent Ligation of the Left Anterior Descending Coronary Artery in Mice: A Model of Post-myocardial Infarction Remodelling and Heart Failure

Heart failure is a syndrome in which the heart fails to pump blood at a rate commensurate with cellular oxygen requirements at rest or during stress. It is characterized by fluid retention, shortness of breath, and fatigue, in particular on exertion. Heart failure is a growing public health problem, the leading cause of hospitalization, and a major cause of mortality. Ischemic heart disease is the main cause of heart failure.
Ventricular remodelling refers to changes in structure, size, and shape of the left ventricle. This architectural remodelling of the left ventricle is induced by injury (e.g., myocardial infarction), by pressure overload (e.g., systemic arterial hypertension or aortic stenosis), or by volume overload. Since ventricular remodelling affects wall stress, it has a profound impact on cardiac function and on the development of heart failure. A model of permanent ligation of the left anterior descending coronary artery in mice is used to investigate ventricular remodelling and cardiac function post-myocardial infarction. This model is fundamentally different in terms of objectives and pathophysiological relevance compared to the model of transient ligation of the left anterior descending coronary artery. In this latter model of ischemia/reperfusion injury, the initial extent of the infarct may be modulated by factors that affect myocardial salvage following reperfusion. In contrast, the infarct area at 24 hr after permanent ligation of the left anterior descending coronary artery is fixed. Cardiac function in this model will be affected by 1) the process of infarct expansion, infarct healing, and scar formation; and 2) the concomitant development of left ventricular dilatation, cardiac hypertrophy, and ventricular remodelling.
Besides the model of permanent ligation of the left anterior descending coronary artery, the technique of invasive hemodynamic measurements in mice is presented in detail.

Heart failure is the leading cause of hospitalization and a major cause of mortality. A model of permanent ligation of the left anterior descending coronary artery in mice is applied to investigate ventricular remodelling and cardiac dysfunction post-myocardial infarction. The technique of invasive hemodynamic measurements in mice is presented.

左冠状动脉前降支的小鼠结扎:对心肌梗死后重塑和心衰模型

Heart failure is a syndrome in which the heart fails to pump blood at a rate commensurate with cellular oxygen requirements at rest or during stress. It ...

Ultrasound Based Assessment of Coronary Artery Flow and Coronary Flow Reserve Using the Pressure Overload Model in Mice

Transthoracic Doppler echocardiography (TTDE) is a clinically useful, noninvasive tool for studying coronary artery flow velocity and coronary flow reserve (CFR) in humans. Reduced CFR is accompanied by marked intramyocardial and pericoronary fibrosis and is used as an indication of the severity of dysfunction. This study explores, step-by-step, the real-time changes measured in the coronary flow velocity, CFR and systolic to diastolic peak velocity (S/D) ratio in the setting of an aortic banding model in mice. By using a Doppler transthoracic imaging technique that yields reproducible and reliable data, the method assesses changes in flow in the septal coronary artery (SCA), for a period of over two weeks in mice, that previously either underwent aortic banding or thoracotomy. 
During imaging, hyperemia in all mice was induced by isoflurane, an anesthetic that increased coronary flow velocity when compared with resting flow. All images were acquired by a single imager. Two ratios, (1) CFR, the ratio between hyperemic and baseline flow velocities, and (2) systolic (S) to diastolic (D) flow were determined, using a proprietary software and by two independent observers. Importantly, the observed changes in coronary flow preceded LV dysfunction as evidenced by normal LV mass and fractional shortening (FS). 
The method was benchmarked against the current gold standard of coronary assessment, histopathology. The latter technique showed clear pathologic changes in the coronary artery in the form of peri-coronary fibrosis that correlated to the flow changes as assessed by echocardiography. 
The study underscores the value of using a non-invasive technique to monitor coronary circulation in mouse hearts. The method minimizes redundant use of research animals and demonstrates that advanced ultrasound-based indices, such as CFR and S/D ratios, can serve as viable diagnostic tools in a variety of investigational protocols including drug studies and the study of genetically modified strains.

Coronary flow reserve (CFR) is useful for assessment of myocardial oxygen demand and evaluation of cardiovascular risk. This study establishes a step-by-step transthoracic Doppler echocardiographic (TTDE) method for longitudinal monitoring of the changes in CFR, as measured from coronary artery in mice, under the experimental pressure overload of aortic banding.

冠脉流量和冠状动脉血流储备用小鼠压力超负荷基于模型的超声评估

Transthoracic Doppler echocardiography (TTDE) is a clinically useful, noninvasive tool for studying coronary artery flow velocity and coronary flow ...

Surgical Approach for Middle Cerebral Artery Occlusion and Reperfusion Induced Stroke in Mice

Stroke is a leading cause of death worldwide and continues to be one of the major causes of long-term adult disabilities. About 87% of strokes are ischemic in origin and occur in the territory of the middle cerebral artery (MCA). Currently the only Food and Drug Administration (FDA) approved drug for the treatment of this devastating disease is tissue plasminogen activator (tPA). However, tPA has a small therapeutic window for administration (3 - 6 hr), and is only effective in 4% of the patients who actually receive it. Current research focuses on understanding the pathophysiology of stroke in order to find potential therapeutic targets. Thus, reliable models are crucial, and the MCA occlusion (MCAo) model (also termed the intraluminal filament or suture model) is deemed to be the most clinically relevant surgical model of ischemic stroke, and is fairly non-invasive and easily reproducible. Typically the MCAo model is used with rodents, especially with mice due to all the genetic variations available for this species. Here we describe (and present in the video) how to successfully perform the MCAo model (with reperfusion) in mice to generate reliable and reproducible data.

In order to understand the pathophysiology of stroke, it is important to use reliable models. This paper will describe one of the most frequently used stroke models in mice, termed the middle cerebral artery occlusion (MCAo) model (also termed the intraluminal filament or suture model) with reperfusion.

对大脑中动脉闭塞再灌注损伤诱发中风小鼠的手术方法

Stroke is a leading cause of death worldwide and continues to be one of the major causes of long-term adult disabilities. About 87% of strokes are ...

Use of a Low-flow Digital Anesthesia System for Mice and Rats

A traditional vaporizer depends on flowing gas and atmospheric pressure for passive anesthetic vaporization. Newly developed direct injection vaporizers utilize a syringe pump to directly administer volatile anesthetics into a gas stream. Unlike a traditional vaporizer, it can be used at very low flow rates, making it ideal for use on mice and rats. 
The equipment's capability to use low flow rates could result in a substantial cost savings due to the reduced need for anesthetic agents, compressed gas, and charcoal scavenging filters1. A lower flow rate means less waste of anesthetic gas and likely reduces the risk of anesthetic exposure to laboratory personnel. Thus, the high levels of precision and safety associated with direct injection vaporizers, along with a reduced need for anesthetic agents, compressed gas, and charcoal filters are beneficial for research requiring small animal anesthesia. 
The goal of this protocol is to demonstrate the use of a syringe-driven direct injection vaporizer as part of a digital, low-flow anesthesia system. The direct injection vaporizer is capable of accurately delivering anesthesia at very low flow rates compared to a traditional vaporizer, making it a promising alternative for controlled gas anesthetic delivery to rodents.

Here, we present a protocol to more safely and efficiently administer anesthetic gas to mice using a digital, low flow anesthesia system utilizing a syringe-driven direct injection vaporizer.

低流量数字麻醉系统的小鼠和大鼠的用途

A traditional vaporizer depends on flowing gas and atmospheric pressure for passive anesthetic vaporization. Newly developed direct injection vaporizers ...

Identifying Coronary Artery Calcification on Non-gated Computed Tomography Scans

Coronary artery calcification (CAC) provides an objective measure of coronary artery disease and can readily be identified on non-gated computed tomography (CT) scans with a high correlation with gated cardiac CT scans. This standardized protocol takes a step-wise approach to not only optimizing an image for the identification of calcification but also to distinguishing CAC from other common causes of calcification in the cardiac silhouette. Recognition of CAC on non-gated CT scans helps to identify a very powerful prognostic factor that can influence therapeutic interventions or downstream diagnostic testing without requiring a gated cardiac scan. These non-gated CT scans are often acquired as part of the routine care of the patient, and this data is readily available without another dose of&#160;ionizing radiation. This protocol allows for the precise and accurate extraction of this data for the purposes of retrospective data analysis in clinical research studies, but also in the clinical evaluation and management of patients.

Here, we present a protocol to reliably and systematically identify coronary artery calcification (CAC) on non-gated computed tomography (CT) scans of the chest or abdomen. CAC provides an objective measure of coronary artery disease for both research and clinical purposes.