这项工作得到了教育、文化、体育、科学和技术部（MEXT）的科学研究援助赠款（18K09424，东芝库里原和20K18393对三和裕一郎）的支持。

这里描述的所有方法都得到了庆应大学医学院机构动物护理和使用委员会（IACUC）的批准。
1. 准备手术器械和动物
<ol><li>高压外科手术器械，并保持他们在70%的乙醇。在每一次新的外科手术之前，清洁手术器械小心使用70%的乙醇。</li>
	<li>在特定无病原体 （SPF） 室中准备雄性 BALB/cAJc1 小鼠（6 周大，26-28 公斤），以便在手术前、手术期间和手术后保持无菌状态。</li>
</ol>2. 瞬态双边常见胡萝卜动脉闭塞（tBCCAO）
<ol><li>通过腹内注射将鼠标置于麻醉下，结合中佐兰（40微克/100微升）、梅德托米丁（7.5微克/100微升）和丁醇酸酸盐（50微克/100微升），称为"MMB"，如前述的8，9。抓住老鼠的后皮，防止老鼠撞到眼睛，直到老鼠完全麻醉。<ol>
<li>判断麻醉的深度，捏鼠标脚趾，直到它没有反应，其中的方法通常用于检查完整的麻醉10。 注:一般来说，小鼠入睡需要不到5分钟。适当的全身麻醉配方可能因机构而异。</li>
	</ol>
</li>
	<li>将一滴0.1%纯化的透明质钠眼药水溶液涂抹在眼睛上，防止麻醉下眼睛干燥。</li>
	<li>将鼠标放在它的背上，用胶带固定鼠标的爪子。</li>
	<li>手术前使用70%的乙醇对老鼠的颈部区域进行消毒。 注:毛皮的额外剪裁没有进行，因为这可能导致随后的皮肤炎症11，12。</li>
	<li>用刀片（图1）对颈部进行下垂切口。 注:切口需要在颈部、胸骨和气管之间的中线进行。</li>
	<li>使用两个钳子小心地分离两个唾液腺，并动员它们来可视化潜在的CPA。</li>
	<li>在不损害其结构的情况下，小心地将右 CCA 与各自的血管神经和伴随的静脉隔离，并将两根 6-0 丝绸缝合线置于 CCA 下。将两条领带紧紧地系住，以阻止血流（图1）。 注:在手术过程中，小静脉可能会受损。如果看到出血，需要擦拭才能清楚地显示CCA。</li>
	<li>从各自的血管神经和伴随的静脉中仔细查找左CCA，而不会伤害其结构，并通过夹子将左CCA遮挡 2 秒（图 1）。 注:需要将 6-0 丝缝针放在左 CCA 下，以标记夹紧的部位。</li>
	<li>左CCA重新打开后，用6-0丝缝合颈部的缝合伤口，并在颈部涂抹抗生素（50 μL），以抑制细菌感染。 注:在左CCA重新打开时，请轻轻取下夹子以避免损坏动脉壁。</li>
	<li>将0.75毫克/千克盐酸阿提帕米佐尔注射到鼠体内，帮助小鼠迅速从深度麻醉中恢复过来。将鼠标返回带预热垫的鼠标笼中。 注意:不要让鼠标无人看管，直到鼠标恢复足够的意识，以保持体面休养。</li>
	<li>将 0.4 毫克/千克的布托帕诺酸酸注射到鼠标上，用于管理鼠标醒来时的疼痛。 注:协议可在此处暂停。作为成功tBCCAO的第一个提示，可以观察到鼠标的眼睑下垂（图2）。</li>
	<li>对于安乐死，向小鼠注射3倍的MB混合物，并牺牲它们进行实验。</li>
</ol>3. 一般观察（存活率和眼睑下垂）
<ol><li>手术后，检查所有死因的存活率在第0天（手术后），1，3和7。</li>
	<li>评估眼睑下垂 4 点评级尺度: 1 = 无下垂， 2 = 轻度下垂 （约 50%）， 3 = 严重下垂 （超过 50%）， 4 = 眼睛放电严重下垂。</li>
</ol>4. 视网膜输血
<ol><li>注射200μL的FITC-dextran（25毫克/mL）到小鼠的左心室，这是通常用于观察血液灌注小鼠视网膜血管13，14。</li>
	<li>循环后2分钟，将眼睛核化，固定在4%的准甲醛中1小时。视网膜被仔细获得和平装，如先前描述的15，并通过荧光显微镜检查。</li>
	<li>以 4 倍的放大倍率拍摄视网膜整个坐骑的照片，并使用合并分析仪合并成一个单个，以前描述的16。</li>
	<li>通过 NIH 斐济/ImageJ 软件中的容器分析工具测量注入区域。</li>
</ol>5. 西方污点
<ol><li>3和6小时后，tBCCAO，获得小鼠的眼睛，并立即转移到含有冷PBS的培养皿，以隔离视网膜。</li>
	<li>视网膜隔离后，进行西印，如先前描述的9。</li>
	<li>与抗体一起孵化，用于缺氧诱发因子-1+（HIF-1+;一般缺氧标记）和β-Actin（内部负荷控制），然后孵化HRP结合的次要抗体。通过化学发光可视化信号。</li>
</ol>6. 定量 PCR （qPCR）
<ol><li>6，12和24小时后tBCCAO，处理获得的视网膜qPCR，如先前描述的17。</li>
	<li>通过实时PCR系统执行qPCR。所使用的底漆列在 表 1中。通过ΔΔCT 方法计算不同成绩单水平之间的折叠变化。</li>
</ol>7. 免疫化学（IHC）
<ol><li>3天后tBCCAO，获得小鼠的眼睛，并嵌入石蜡。</li>
	<li>用微切除术切割石蜡嵌入的眼睛，以获得眼部。</li>
	<li>去石蜡和染色眼睛部分的5μm厚度，如先前描述的13。</li>
	<li>与胶质纤维酸性蛋白（GFAP;星形细胞和网膜中的穆勒细胞的可靠标记）的抗体一起孵化过夜，然后孵化亚历克萨氟555结合二次抗体。</li>
	<li>使用DAPI（4+，6-迪亚米迪诺-2-苯丙酮）染色视网膜中的细胞核。通过荧光显微镜可视化信号。</li>
	<li>按 4 分评级等级评估形态评分，如之前描述的 13、18:0 = 无信号、1 = 在胶质细胞层 （GCL） 中很少有正胶质端脚、2 = 从 GCL 到外核层 （ONL） 的标记过程很少，以及从 GCL 到 ONL 的大多数标记过程。</li>
</ol>8. 电视网膜成像（ERG）
<ol><li>3和7天后tBCCAO，执行ERG使用甘兹费尔德圆顶，采集系统和LED刺激器，如前所述9。</li>
	<li>经过一夜的黑暗适应后，在昏暗的红灯下用MB组合麻醉小鼠。</li>
	<li>使用0.5%热带酰胺和0.5%苯肾上腺素的混合溶液来延长瞳孔。</li>
	<li>将活动电极放在隐形眼镜上，并将参考电极放置在口腔中。</li>
	<li>从每只动物的两只眼睛获得ERG响应。</li>
	<li>用各种刺激记录黑暗适应下的滑板反应。</li>
	<li>测量波从基线到波的最低点的振幅。</li>
	<li>测量 b 波的振幅，从波的最低点到 b 波的峰值。</li>
	<li>使用热垫在手术过程中保持所有小鼠的温暖。</li>
</ol>9. 光学连贯断层扫描 （OCT）
<ol><li>tBCCAO后2周，使用SD-OCT系统执行OCT，如先前报道的8，9。</li>
	<li>在测量中，通过0.5%的热带酰胺和0.5%的苯肾上腺素的混合溶液，让小鼠患上甲虫病，并通过MB的混合物进行全身麻醉。</li>
	<li>从赤道片的面对面扫描中获取 B 扫描图像。</li>
	<li>检查视网膜在0.2，0.4和0.6毫米从视神经头。</li>
	<li>测量视网膜厚度从视网膜神经纤维层 （NFL） 到外部限制膜 （ELM），并将测量值的平均值视为单个鼠标的视网膜厚度。</li>
	<li>将结果绘制为蜘蛛图。</li>
</ol>

作者没有什么可透露的。

在这项研究中，我们已经表明，tBCCAO，使用简单的缝合和夹子，可以诱导视网膜缺血和伴随视网膜功能障碍。此外，我们已证明，我们目前的协议，开发视网膜缺血小鼠模型是更容易和更快相比，其他以前的协议，开发视网膜缺血损伤模型2，3，7。
从解剖学上讲，左右脑动脉可以通过后沟通动脉（PCAs）连接，这些动脉在威利斯圆圈内提供辅助循环，以维持对中枢神经系统的充足血液供应，防止单个血管24、25（图1）的闭塞或狭窄导致流量中断。李等人证明视网膜输血可能是10分钟延迟（这不是整个封锁视网膜中的视网膜输液）由永久单边CCAO在C57BL6小鼠13。这意味着，CCAO诱导视网膜缺血与威利斯圈子中的抵押流通条件密切相关。C57BL6 是 BCCAO 在七种小鼠菌株中对脑缺血最易感染的鼠株，包括我们目前研究的鼠株 BALB26。由于C57BL6中威利斯的圆圈不完整，两个CPA的脑血供应中断导致中枢神经系统严重受损，最终导致死亡。此外，在我们的初步研究中，我们未能诱导C57BL6中的tBCCAO，因为几乎所有的小鼠（约80%）手术后3天内死亡（补充图4）。因此，我们应用tBCCAO到另一个鼠菌株BALB为我们目前的研究。
为了在我们的BALB模型中诱发急性视网膜缺血损伤，右CCA被永久搁置，左CCA被应用通过瞬态闭塞来增加急性视网膜缺血应激。这是因为老鼠不能容忍由永久BCCAO引起的缺血应激不像老鼠谁拥有威利斯27的完整圆圈。接下来，我们试图优化闭合时间:左CCAO（0-20秒），因为遮挡时间被认为是影响中枢神经系统的缺血损伤的关键因素之一，并直接与实验模型28，29的存活率连接。我们发现BALB小鼠的存活率以闭塞时间依赖的方式下降（补充图4）。左CCA超过10秒的遮挡显示死亡率严重较高（超过50%），而左CCA的封闭2秒或无遮挡（或单边CCAO）显示存活率相对较高（超过80%）。因此，我们排除了进一步实验的组（10秒和20秒），因为无法进行高效和具有成本效益的实验。接下来，我们检查了左CCA的闭塞2秒或没有遮挡（或单边CCAO）是否会诱发视网膜缺氧。HIF-1®是一种主要的调节器，在缺氧反应中发挥作用，并在缺氧条件下稳定下来。在这方面，HIF-1®稳定性已被用作缺氧的一般分子生物学标记。我们无法检测到单边CCAO组的网膜HIF-1®稳定（补充图5）。有趣的是，我们可以检测到HIF-1®稳定在tBCCAO组2秒（图3）。这意味着视网膜缺氧应激可能由 BALB 小鼠的 2 秒 tBCCAO 诱导。因此，根据手术后的高存活率和通过HIF-1®稳定诱导视网膜缺血，我们最终选择了2秒的夹紧时间供我们研究。
虽然正确的CCA在tBCCAO手术的小鼠中被永久排除，但在FITC-dextran系统循环2分钟后，在右网膜中部分检测到输血（补充图1）。此外，我们发现，在单侧CCAO操作的BALB小鼠的右网膜中未发现HIF-1®稳定性的变化。这种现象可以通过威利斯圆的附带循环的影响来解释，以维持对网膜的血液供应（图1）。尽管我们无法清楚地理解左瞬态CCAO对右网膜输血的影响，但瞬态左CCAO和永久右CCAO可能会加剧右网膜急性缺氧侮辱，这从tBCCAO（图3）后右网膜HIF-1®表达的重大变化就证明了这一点。此外，小鼠的存活率取决于左CCA的闭合时间。综合起来，视网膜缺血应激的强度可以通过左CCAO控制。
下垂眼睑的表型已被建议为严重神经系统疾病的呈现迹象或病理生理症状，特别是缺血性中风31，32。与下垂的眼睑相关的肌肉是升高器苍白的优越33。这种肌肉是由横向苍白动脉提供的，这是从OpA衍生的分支之一。因此，当提供视网膜的OpA受到影响时，可以看到眼睑下垂。在 MCAO 小鼠模型34中观察到眼睑下垂，这也在我们的 tBCCAO 模型中复制。此外，我们描述了当左CCA的遮挡时间更长时眼睑下垂变得严重（图2和补充图6）。这意味着眼睑下垂的严重程度（间接称为视网膜缺血应激的强度）可能取决于左CCA的闭合时间。
视网膜功能障碍是视网膜缺血性视网膜病变的结果之一，包括35号小鼠的BCCA狭窄和36号大鼠的BCCAO。我们发现b波的振幅在tBCCAO操作的小鼠中降低。先前的几项研究表明，MCAO在手术后也导致b波振幅的降低37，38。b波反映了视网膜内层细胞的生理状况，包括双极细胞和穆勒细胞39。此外，在tBCCAO之后，在内部视网膜层中检测到穆勒细胞的活性胶质疏松症。这一结果也复制在MCAAO模型40，41和其他CCAO模型13，42。综合起来，这意味着内视网膜功能障碍可能由tBCCAO诱导。据报道，视网膜厚度暂时增加急性视网膜缺血43，44。我们还在tBCCAO操作的小鼠中复制了这一发现。这些数据表明，tBCCAO对血液循环的损害可能到达视网膜，最终影响视网膜层。
对于一致的结果，麻醉时间和手术时间，以及其他因素，如重量和年龄的实验模型及其体温在手术期间和手术后应标准化45。特别需要注意在整个实验观察期间保持小鼠的体温。这是因为体温过低可能会有先决条件的影响，并干扰缺血效应由tBCCAO46。尽管我们在实验中无法测量老鼠的确切体温，但我们使用加热垫加热老鼠，直到老鼠恢复足够的意识。此外，我们比较了tBCCAO操作的小鼠和假操作的小鼠，以控制无法控制的因素的潜在混淆效应。
小鼠菌株可能是诱发视网膜缺血损伤的一个重要可变因素。小鼠菌株中威利斯圆的显著变化可能导致脑缺血（包括视网膜缺血症47） 的意外减少或诱导，从而可能导致结果的变异。当需要应用其他小鼠菌株时，建议调整夹紧时间，以治疗成功的 tBCCAO 诱发的缺血性视网膜病变。
一般来说，中风或其他脑损伤事件总是伴随着暂时或永久的毒视损失48。迄今为止，MCAO小鼠模型被广泛用于中风研究。由于 Opa 起源于 MCA 的起源，因此 MCA 血液流动的任何障碍都阻碍了到网膜的流动。视网膜缺血首先由MCAO37在老鼠中表现出来。后来，同样的视网膜缺血模型被应用到小鼠49。然而，对于这个程序，闭塞需要超过60分钟，找到一个遮挡部位是极其困难的，因为MCA被埋在大脑深处。此外，MCAO 的灯丝尺寸和插入长度极大地决定了手术的成功。这些额外的可变因素导致手术后缺血结果的变异性。虽然 tBCCAO 和 MCAO 之间需要直接比较研究，但我们在本研究中描述了我们实验模型的有益特征:封闭时间短、实验过程简单且极易获得的遮挡点。此模型可以解决 MCAO 模型中出现的问题。
虽然使用视网膜缺血小鼠模型对研究视网膜缺血损伤有很大的益处，但这种方法仍有局限性。由于手术切口进入颈部，唾液腺的分离和在正确的CCA与缝合物的遮挡必须适用于手术，伴随的组织中断可以引起相关的炎症系统或至少在当地。这些问题部分地使用假手术小鼠解决，所有手术步骤都是在没有tBCCAO的情况下进行的。另一个问题是管理手术期间和手术后发生的疼痛的要求。在我们的研究中，通过注射丁丙醇酸酯溶液（一种合成衍生的阿片类拮抗剂镇痛剂）来预防小鼠的痛苦管理。重要的是要知道，使用不同类型的麻醉剂和镇痛药可以破坏tBCCAO对视网膜缺血的影响。这种方法的另一个局限性（连同目前使用的其他模型的方法）是，它不能提供与人类心血管视网膜疾病相关的病理学的完美模拟。迄今为止，用于此类实验的老鼠模型并不患有人类缺血性视网膜病变的共病，主要是代谢综合征，如糖尿病50。目前小鼠模型中不存在的这种并发症可能会对缺血性视网膜病变发展的病理途径产生负面的协同效应。因此，在解释当前使用的实验模型（包括我们的 tBCCAO 鼠标模型）的结果时，应考虑到这一点。为了更好地了解人类缺血性视网膜病变的病理生理机制，我们的模型可以与其他病理因素相结合，如链球菌素注射51或高脂肪饮食补充剂52，用于发展缺血性糖尿病视网膜病变。最后，即使我们在tBCCAO手术的小鼠中表现出视网膜输血减少，我们也无法清楚地理解左瞬态CCAO对右视网膜输血的影响。这个问题可以解决使用激光多普勒，这是通常用来确认，封闭已经发生，缺血已经发生在体内实时53，54。该技术可用于更好地了解单个 tBCCAO 操作的鼠标中的视网膜缺血，了解威利斯圆圈中的附带循环。
尽管有这些局限性，我们在这里描述的tBCCAO方法代表了在小鼠中产生视网膜缺血的有效方法。通过tBCCAO研究视网膜变化有助于解开人类缺血性视网膜病变的病理机制。此外，我们希望tBCCAO小鼠模型可用于体内药物筛选。

视网膜是一种神经感官组织，用于视觉功能。由于视觉功能需要大量的氧气，视网膜被称为身体中对氧气要求最高的组织之一。由于氧气通过血管输送，网膜易患血管疾病。各种血管疾病，如糖尿病视网膜病变和视网膜血管（静脉或动脉）闭塞，可诱发视网膜缺血。为了研究视网膜缺血的病理机制，认为有必要对视网膜缺血进行可重复和临床相关的实验模型。通过插入内脏丝进行中脑动脉闭塞（MCAO）是开发实验性脑缺血2、3体内啮齿动物模型的最普遍方法。由于眼动脉（OpA）接近MCA，MCAO模型也同时用于了解视网膜缺血的病理生理学4，5，6。为了诱导脑缺血和视网膜缺血，长丝通常通过普通胡萝卜动脉 （CCA） 或外部胡萝卜动脉 （ECA） 的切口插入。这些方法很难执行，需要很长时间才能完成手术（一只小鼠超过60分钟），并导致手术后结果的高变异性7。制定更好的模式以改善这些关切仍然很重要。
在这项研究中，我们只是使用短的瞬态双边CCA闭塞（tBCCAO）与针头和夹子诱导视网膜缺血在小鼠，并分析了视网膜缺血损伤的典型结果。在此视频中，我们将演示 tBCCAO 程序。

<table><tbody><tr><td>Atipamezole hydrochloride</td><td>Zenoaq</td><td>Antisedan</td><td>For anti-anesthesia</td></tr><tr><td>Applied Biosystems 7500 Fast</td><td>Applied Biosystems</td><td>-</td><td>For qPCR</td></tr><tr><td>Butorphanol tartrate</td><td>Meiji Seika Pharma</td><td>Vetorphale</td><td>For anesthesia</td></tr><tr><td>BZ-II Analyzer</td><td>KEYENCE</td><td>-</td><td>For an image merge</td></tr><tr><td>BALB/cAJc1</td><td>CLEA</td><td>-</td><td>Mouse strain</td></tr><tr><td>&amp;beta;-Actin (8H10D10) Mouse mAb</td><td>CST</td><td>3700</td><td>For western blot</td></tr><tr><td>Clamp Forcep</td><td>World Precision Instruments</td><td>WPI 500451</td><td>For surgery</td></tr><tr><td>Dumont forceps #5</td><td>Fine Science Tools</td><td>11251-10</td><td>For surgery</td></tr><tr><td>DAPI solution</td><td>Dojindo</td><td>340-07971</td><td>For IHC</td></tr><tr><td>Envisu SD-OCT system</td><td>Leica</td><td>R4310</td><td>For OCT</td></tr><tr><td>FITC-dextran</td><td>Merk</td><td>FD2000S</td><td>For retinal blood perfusion</td></tr><tr><td>Fluorescence microscope</td><td>KEYENCE</td><td>BZ-9000</td><td>For fluorescence detection</td></tr><tr><td>Gatifloxacin hydrate</td><td>Senju Pharmaceutical</td><td>Gachifuro</td><td>For anti-bacterial infection</td></tr><tr><td>GFAP Monoclonal Antibody (2.2B10)</td><td>Thermo</td><td>13-0300</td><td>For IHC</td></tr><tr><td>Heating pad</td><td>Marukan</td><td>RH-200</td><td>For surgery</td></tr><tr><td>HIF-1&amp;alpha; (D1S7W) XP Rabbit mAb</td><td>CST</td><td>36169</td><td>For western blot</td></tr><tr><td>ImageQuant LAS 4000 mini</td><td>GE Healthcare</td><td>-</td><td>For chemiluminescence</td></tr><tr><td>Midazolam</td><td>Sandoz K.K</td><td>SANDOZ</td><td>For anesthesia</td></tr><tr><td>Microtome Tissue-Tek TEC 6</td><td>Sakura</td><td>-</td><td>For sectioning</td></tr><tr><td>Medetomidine</td><td>Orion Corporation</td><td>Domitor</td><td>For anesthesia</td></tr><tr><td>Needle holder</td><td>Handaya</td><td>HS-2307</td><td>For surgery</td></tr><tr><td>PuREC</td><td>MAYO Corporation</td><td>-</td><td>For ERG</td></tr><tr><td>Scissor</td><td>Fine Science Tools</td><td>91460-11</td><td>For surgery</td></tr><tr><td>Sodium hyaluronate</td><td>Santen Pharmaceutical</td><td>Hyalein</td><td>For eye lubrication</td></tr><tr><td>Tropicamide/Penylephrine hydrochloride</td><td>Santen Pharmaceutical</td><td>Mydrin-P</td><td>For mydriasis</td></tr><tr><td>6-0 silk suture</td><td>Natsume</td><td>E12-60N2</td><td>For surgery</td></tr></tbody></table>

a murine model of ischemic retinal injury induced by transient bilateral common carotid artery occlusion

多种血管疾病，如糖尿病视网膜病变、视网膜静脉或动脉闭塞以及眼缺血综合征可导致视网膜缺血。为了研究视网膜缺血的病理机制，需要开发相关的实验模型。从解剖学上讲，主要的视网膜供血血管是眼动脉 （OpA）， OpA 起源于普通胡萝卜动脉 （CCA） 的内胡萝卜动脉。因此，CCA的中断可以有效地导致视网膜缺血。在这里，我们建立了视网膜缺血的鼠标模型，通过瞬态的双边常见胡萝卜素动脉闭塞（tBCCAO），用6-0丝缝合右CCA，并通过夹子暂时将左CCA遮挡2秒，并表明tBCCAO可以诱发急性视网膜缺血，导致视网膜功能障碍。目前的方法通过仅使用手术针头和夹子来减少对手术器械的依赖，缩短了闭塞时间，以尽量减少意外的动物死亡，这在中脑动脉闭塞小鼠模型中经常看到，并保持常见视网膜缺血结果的可重复性。该模型可用于研究小鼠缺血视网膜病变的病理生理学，并进一步用于体内药物筛选。

在FITC-dextran系统循环2分钟后，检查了假手术小鼠和tBCCAO手术小鼠左视网膜和右视网膜的视网膜血管（补充图1）。FITC-dextran在假手术小鼠的视网膜和tBCCAO操作的小鼠的左视网膜中完全可见，而在tBCCAO操作的小鼠的右视网膜中部分可检测到。
在tBCCAO之后，对眼睑下垂进行了检查（图2）。右眼显示温和（得分2;75%）和严重的眼睑（分数3和4:25%）下垂，而左眼没有下垂（得分1:93.75%）除了一只鼠标（分数2;6.25%）。虽然在tBCCAO手术的小鼠中没有发现眼睑严重下垂的情况，但我们可以看到一只小鼠出现这种表型（得分4;6.25%）。
组织中的氧气状态降低导致HIF-1®的稳定，并诱导一些对缺氧反应的基因，如EPO、VEGF和BNIP319、20、21。 首先，使用一般缺氧标记HIF-1®的分子生物缺氧通过西方印迹（图3）进行评估。在 tBCCAO 之后的 3 小时和 6 小时内，右网膜显著观察到 HIF-1® 表达的增加。接下来，通过qPCR（补充图2）对对缺氧反应基因的表达进行评估。在 tBCCAO 之后的 6 小时内，对缺氧反应的基因表达没有显著变化。tBCCAO 12 小时后，我们发现Binp3表达明显增加，右视网膜显示Epo表情略有增加。在 tBCCAO 之后的 24 小时内，我们还可以发现右视网膜中的Epo表情略有增加，尽管它在统计学上没有显著性。在 tBCCAO 操作的小鼠中，Vegf的表达方式在 6 到 24 小时内没有改变。
视网膜反应性胶质疏松症在tBCCAO（图4）3天后被检查，因为天体细胞和穆勒细胞等胶质疏松症与视网膜缺血症22密切相关。GFAP已被广泛用于检测星形细胞和髓膜细胞在网膜23。右视网膜中GFAP标签的形态评分在假手术小鼠的视网膜和tBCCAO操作的小鼠的左视网膜中最高。基于 GFAP 表达式的本地化，GFAP 标签的形态变化被认为反映了 Müller 细胞的激活。
ERG用于检查视网膜功能障碍后tBCCAO（图5）。右眼b波的振幅在tBCCAO后3天和7天急剧下降。但是，右眼波浪的振幅没有显著变化。说到左眼，我们看不到a波和b波的振幅有任何变化（补充图3）。
我们执行 OCT 以确定 tBCCAO （图 6）后视网膜厚度的改变。右眼视网膜厚度在 tBCCAO 后 2 周显著增加，而 tBCCAO 和假手术小鼠的左眼视网膜厚度没有差异。
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61865/61865fig01.jpg"> 图1:威利斯圈子中模型程序和血液循环的示意图。示意图图显示了 tBCCAO 诱导的视网膜缺血小鼠模型程序和视网膜的血液循环。CCA、ECA、ICA、PCA 和 OpA 分别代表常见的胡萝卜动脉、外部胡萝卜动脉、内胡萝卜动脉、后沟通动脉和眼动脉。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/61865fig01large.jpg" target="_blank">请点击这里查看此数字的较大版本。</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/61865/61865fig02.jpg"> 图2:眼睑在tBCCAO后下垂。根据参考图像，对眼睑下垂的严重程度进行了 4 分评分评估:1 = 无下垂，2 = 轻度下垂（+50% 下垂）、3 = 严重下垂（超过 50% 下垂）和 4 = 眼睛放电严重下垂。眼睑下垂是在tBCCAO之后观察到的，并在实验观察期间保持。结果（沙姆:n=10，tBCCAO:n=16）被绘制为散点图。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/61865fig02large.jpg" target="_blank">请点击这里查看此数字的较大版本。</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/61865/61865fig03.jpg"> 图3:HIF-1*在tBCCAO之后稳定。HIF-1+和β-Actin的代表性免疫和定量分析（组为小时3;假:n = 3，tBCCAO:n = 6和组为小时6;假和tBCCAO:n =6）表明HIF-1+在tBCCAO后3小时和6小时稳定在右视网膜中。*P和lt:0.05。这些数据使用学生 的t-test进行分析，并呈现为平均值±标准偏差。L 和 R 分别代表左侧和右侧网膜。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/61865fig03large.jpg" target="_blank">请点击这里查看此数字的较大版本。</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/61865/61865fig04.jpg"> 图4:tBCCAO后的反应性胶质疏松症。视网膜（sham: n = 4， tBCCAO: n = 4） 的代表性下垂部分和通过形态评分 （0-3） 对 GFAP 标签 （红色） 的定量分析表明，GFAP 标签（主要限于 NFL+GCL）扩展到整个内层，从 GCL 扩展到右视网膜中的 ONL（白色箭头）。比例尺条，50μm。DAPI（蓝色）用于染色网膜中的细胞核。NFL、GCL、IPL、INL和上L分别代表神经纤维层、结石细胞层、内质层、内核层和外核层。这些数据使用学生 的t-test进行分析，并呈四分位数，即第25和第75个百分位。*P和lt:0.05。L 和 R 分别代表左侧和右侧网膜。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/61865fig04large.jpg" target="_blank">请点击这里查看此数字的较大版本。</a>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/61865/61865fig05.jpg"> 图5:tBCCAO后右眼视觉功能障碍。（A） 黑暗适应ERG的代表波形在tBCCAO后3天和7天进行。刺激强度 （cd.s/m2）: 0.005.（B） 定量分析显示，右眼b波的振幅减少（沙姆:n = 5，tBCCAO:n = 6），而一波的振幅没有改变。*P +lt; 0.05， **P +lt; 0.01.这些数据使用学生 的t-test进行分析，并呈现为平均值±标准偏差。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/61865fig05large.jpg" target="_blank">请点击这里查看此数字的较大版本。</a>
<img alt="Figure 6" class="xfigimg" src="/files/ftp_upload/61865/61865fig06.jpg"> 图6:tBCCAO后视网膜厚度的变化。假视网膜和tBCCAO操作视网膜中的代表性OCT图像和定量分析显示右视网膜视网膜厚度增加（假:n = 4，tBCCAO:n = 8）。左视网膜视网膜厚度没有变化（香:n=4，tBCCAO:n=8）。比例尺条分别为 200 （上） 和 100 （下） μm。*P和lt:0.05。图表水平轴中的值表示距离绿线检测到的视神经头 （0） 远 0.2、0.4 和 0.6 mm。数据使用双向 ANOVA 进行分析，然后进行邦费罗尼后临时测试。蜘蛛图被呈现为平均与±标准偏差。NFL、INL、ONL和ELM分别是神经纤维层、内核层、外核层和外部限制膜。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/61865fig06large.jpg" target="_blank">请点击这里查看此数字的较大版本。</a>
补充图1:tBCCAO后视网膜输血。 经过2分钟的FITC-dextran循环和定量分析后，代表性视网膜平面坐骑图像（每个图像的放大率较高）表明，在假操作小鼠的视网膜和tBCCAO操作的小鼠的左视网膜中都能观察到完全的香水。然而，在tBCCAO手术的小鼠右网膜显示部分输血。这些数据使用学生 的t-test进行分析，并呈现为平均值±标准偏差。L 和 R 分别代表左侧和右侧网膜。比例尺条分别为 800 和 400 μm。 <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/supfig01.jpg" target="_blank">请点击这里下载此数字。</a>
补充图2:tBCCAO后对缺氧反应基因的表达。 定量分析显示，右网膜中的 Bnip3 mRNA表达在tBCCAO后12小时出现瞬时增加，具有统计学意义。 Epo mRNA 表达在 tBCCAO 之后的 24 小时内在右视网膜中呈上升趋势，尽管其值与假操作右视网膜相比没有显著差异。**P.lt:0.01。这些数据使用学生 的t-test进行分析，并呈现为平均值±标准偏差。 <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/supfig02.jpg" target="_blank">请点击这里下载此数字。</a>
补充图3:tBCCAO后左眼的视觉功能。 定量分析表明，左眼a波和b波的振幅没有变化（沙姆:n = 5，tBCCAO:n = 6）。P=0.05。这些数据使用学生 的t-test进行分析，并呈现为平均值±标准偏差。 <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/supfig03.jpg" target="_blank">请点击这里下载此数字。</a>
补充图4:C57BL6和BALB中tBCCAO之后的存活率。 卡普兰-迈尔生存曲线显示，几乎所有小鼠在C57BL6小鼠的tBCCAO之后3天内死亡。当涉及到BALB小鼠时，tBCCAO中较长的夹紧时间会导致动物突然和严重死亡（第7天、20秒的存活率:10%、10秒:20%、2秒:81%和0秒:95%）。 <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/supfig04.jpg" target="_blank">请点击这里下载此数字。</a>
补充图5:HIF-1*单方面CCAO后稳定。 对HIF-1+和β-Actin的代表性免疫和定量分析（沙姆:n = 3，单边CCAO:n =3）表明，HIF-1在单边CCAO3小时后没有稳定在视网膜中。P=0.05。这些数据是使用学生 的t-test进行分析的，并呈±标准偏差的均值。L 和 R 分别代表左侧和右侧网膜。 <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/supfig05.jpg" target="_blank">请点击这里下载此数字。</a>
补充图 6: 长时间夹紧后严重眼睑下垂。 10秒的tBCCAO诱发严重的眼睑下垂，这是由4点评分等级评估:1 = 无下垂，2 = 轻度下垂（约50%），3 = 严重下垂（超过50%），4 = 严重下垂与眼睛放电，如 图2所述。 <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61865/supfig06.jpg" target="_blank">请点击这里下载此数字。</a>

Watch this Scientific Journal Video about A Murine Model of Ischemic Retinal Injury Induced by Transient Bilateral Common Carotid Artery Occlusion at JoVE.com

A Murine Model of Ischemic Retinal Injury Induced by Transient Bilateral Common Carotid Artery Occlusion

在这里，我们描述了一个鼠标模型的视网膜缺血通过瞬态的双边常见的胡萝卜动脉闭塞使用简单的缝合线和夹子。该模型可用于了解心血管异常引起的视网膜缺血的病理机制。

由瞬态双边常见胡萝卜动脉闭塞引起的缺血性视网膜损伤的 Murine 模型

Diverse vascular diseases such as diabetic retinopathy, occlusion of retinal veins or arteries and ocular ischemic syndrome can lead to retinal ischemia. ...

a-murine-model-ischemic-retinal-injury-induced-transient-bilateral

Nanyang Technological University

Research

JoVE Journal

Medicine

7.4K 次观看.  Keio University School of Medicine. 在这里，我们描述了一个鼠标模型的视网膜缺血通过瞬态的双边常见的胡萝卜动脉闭塞使用简单的缝合线和夹子。该模型可用于了解心血管异常引起的视网膜缺血的病理机制。

视频: A Murine Model of Ischemic Retinal Injury Induced by Transient Bilateral Common Carotid Artery Occlusion

Bilateral Common Carotid Artery Occlusion as an Adequate Preconditioning Stimulus to Induce Early Ischemic Tolerance to Focal Cerebral Ischemia

There is accumulating evidence, that ischemic preconditioning - a non-damaging ischemic challenge to the brain - confers a transient protection to a subsequent damaging ischemic insult. We have established bilateral common carotid artery occlusion as a preconditioning stimulus to induce early ischemic tolerance to transient focal cerebral ischemia in C57Bl6/J mice. In this video, we will demonstrate the methodology used for this study.

There is accumulating evidence, that ischemic preconditioning (PC) &#x2013; a non-damaging ischemic challenge to the brain - confers a transient protection to a subsequent damaging ischemic insult. We established bilateral common carotid artery occlusion (BCCAO) as a preconditioning stimulus to induce early ischemic tolerance (IT) to transient focal cerebral ischemia (induced by middle cerebral artery occlusion, MCAO) in C57Bl6/J mice.

双侧颈总动脉闭塞足够的预处理刺激诱导局灶性脑缺血早期缺血耐受

There is accumulating evidence, that ischemic preconditioning - a non-damaging ischemic challenge to the brain - confers a transient protection to a ...

科研

医学

Stereological and Flow Cytometry Characterization of Leukocyte Subpopulations in Models of Transient or Permanent Cerebral Ischemia

Microglia activation, as well as extravasation of haematogenous macrophages and neutrophils, is believed to play a pivotal role in brain injury after stroke. These myeloid cell subpopulations can display different phenotypes and functions and need to be distinguished and characterized to study their regulation and contribution to tissue damage. This protocol provides two different methodologies for brain immune cell characterization: a precise stereological approach and a flow cytometric analysis. The stereological approach is based on the optical fractionator method, which calculates the total number of cells in an area of interest (infarcted brain) estimated by a systematic random sampling. The second characterization approach provides a simple way to isolate brain leukocyte suspensions and to characterize them by flow cytometry, allowing for the characterization of microglia, infiltrated monocytes and neutrophils of the ischemic tissue. In addition, it also details a cerebral ischemia model in mice that exclusively affects brain cortex, generating highly reproducible infarcts with a low rate of mortality, and the procedure for histological brain processing to characterize infarct volume by the Cavalieri method.

Brain myeloid cells characterization following stroke can be performed by stereology using the optical fractionator method, or by a flow cytometric analysis of brain leukocytes suspensions. Both are useful techniques to perform an accurate phenotypical distinction of the main myeloid cell subsets found in the ischemic brain.

白细胞亚群在暂时或永久的脑缺血模型体视学和流式细胞仪鉴定

Microglia activation, as well as extravasation of haematogenous macrophages and neutrophils, is believed to play a pivotal role in brain injury after ...

Performing Permanent Distal Middle Cerebral with Common Carotid Artery Occlusion in Aged Rats to Study Cortical Ischemia with Sustained Disability

Stroke typically occurs in elderly people with a range of comorbidities including carotid (or other arterial) atherosclerosis, high blood pressure, obesity and diabetes. Accordingly, when evaluating therapies for stroke in animals, it is important to select a model with excellent face validity. Ischemic stroke accounts for 80% of all strokes, and the majority of these occur in the territory of the middle cerebral artery (MCA), often inducing infarcts that affect the sensorimotor cortex, causing persistent plegia or paresis on the contralateral side of the body. We demonstrate in this video a method for producing ischemic stroke in elderly rats, which causes sustained sensorimotor disability and substantial cortical infarcts. Specifically, we induce permanent distal middle cerebral artery occlusion (MCAO) in elderly female rats by using diathermy forceps to occlude a short segment of this artery. The carotid artery on the ipsilateral side to the lesion was then permanently occluded and the contralateral carotid artery was transiently occluded for 60 min. We measure the infarct size using structural T2-weighted magnetic resonance imaging (MRI) at 24 hr and 8 weeks after stroke. In this study, the mean infarct volume was 4.5% &#177; 2.0% (standard deviation) of the ipsilateral hemisphere at 24 hr (corrected for brain swelling using Gerriet&#8217;s equation, n = 5). This model is feasible and clinically relevant as it permits the induction of sustained sensorimotor deficits, which is important for the elucidation of pathophysiological mechanisms and novel treatments.

Here we present a protocol to produce permanent distal middle cerebral artery occlusion in elderly female rats with simultaneous occlusion of the carotid arteries to generate large cortical infarcts and sustained deficits. We show confirmation of the lesion size using structural MRI at 24 hr and 8 weeks after stroke.

执行永久远端大脑中与老年大鼠颈总动脉闭塞研究皮层缺血具有持续残疾

Stroke typically occurs in elderly people with a range of comorbidities including carotid (or other arterial) atherosclerosis, high blood pressure, ...

A Mouse Model of Retinal Ischemia-Reperfusion Injury Through Elevation of Intraocular Pressure

Retinal ischemia-reperfusion (I/R) is a pathophysiological process contributing to cellular damage in multiple ocular conditions, including glaucoma, diabetic retinopathy, and retinal vascular occlusions. Rodent models of I/R injury are providing significant insights into mechanisms and treatment strategies for human I/R injury, especially with regard to neurodegenerative damage in the retinal neurovascular unit. Presented here is a protocol for inducing retinal I/R injury in mice through elevation of intraocular pressure (IOP). In this protocol, the ocular anterior chamber is cannulated with a needle, through which flows the drip of an elevated saline reservoir. Using this drip to raise IOP above systolic arterial blood pressure, a practitioner temporarily halts inner retinal blood flow (ischemia). When circulation is reinstated (reperfusion) by removal of the cannula, severe cellular damage ensues, resulting ultimately in retinal neurodegeneration. Recent studies demonstrate inflammation, vascular permeability, and capillary degeneration as additional elements of this model. Compared to alternative retinal I/R methodologies, such as retinal arterial ligation, retinal I/R injury by elevated IOP offers advantages in its&#160;anatomical specificity, experimental tractability, and technical accessibility, presenting itself as a valuable tool for examining neuronal pathogenesis and therapy in the retinal neurovascular unit.

This article describes a procedure for inducing retinal ischemia-reperfusion injury by elevated intraocular pressure in mice. Retinal ischemia-reperfusion injury by elevated intraocular pressure serves to model human pathologies characterized by compromised oxygen and nutrient delivery in the retina, enabling researchers to examine potential cellular mechanisms and treatments for human diseases of the retinal neurovascular unit.

视网膜缺血再灌注损伤的小鼠模型通过眼压升高

Retinal ischemia-reperfusion (I/R) is a pathophysiological process contributing to cellular damage in multiple ocular conditions, including glaucoma, ...

Induction of Ischemic Stroke and Ischemia-reperfusion in Mice Using the Middle Artery Occlusion Technique and Visualization of Infarct Area

Cerebrovascular disease is highly prevalent in the global population and encompasses several types of conditions, including stroke. To study the impact of stroke on tissue injury and to evaluate the effectiveness of therapeutic interventions, several experimental models in a variety of species were developed. They include complete global cerebral ischemia, incomplete global ischemia, focal cerebral ischemia, and multifocal cerebral ischemia. The model described in this protocol is based on the middle cerebral artery occlusion (MCAO) and is related to the focal ischemia category. This technique produces consistent focal ischemia in a strictly defined region of the hemisphere and is less invasive than other methods. The procedure described is performed on mice, given the availability of several genetic variants and the high number of tests standardized for mice to aid in the behavioral and neurodeficit evaluation.

We describe a mouse model of stroke induced by the occlusion of the middle cerebral artery using a silicone coated suture. The protocol can be applied to induce permanent occlusion or a temporary ischemia, followed by reperfusion.

缺血性中风和缺血再灌注小鼠的诱导使用梗塞区的中心动脉闭塞技术和可视化

Cerebrovascular disease is highly prevalent in the global population and encompasses several types of conditions, including stroke. To study the impact of ...

Middle Cerebral Artery Occlusion Allowing Reperfusion via Common Carotid Artery Repair in Mice

The ischemic stroke is a major cause of adult long-term disability and death worldwide. The current treatments available are limited, with only tissue plasminogen activator (tPA) as an approved drug treatment to target ischemic strokes. Current research in the field of ischemic stroke focuses on better understanding the pathophysiology of stroke, to develop and investigate novel pharmaceutical targets. Reliable experimental stroke models are crucial for the progression of potential treatments. The middle cerebral artery occlusion (MCAO) model is clinically relevant and the most frequently used surgical model of ischemic stroke in rodents. However, the outcomes of this model, such as lesion volume, are associated with high levels of variability, particularly in mice. The alternative MCAO model described here allows the reperfusion of the common carotid artery (CCA) and the increased perfusion of the middle cerebral artery (MCA) territory, using a tissue pad with fibrinogen-based sealant to repair the vessel, and the improved welfare of the mice by avoiding external carotid artery (ECA) ligation. This reduces the reliance on the Circle of Willis, which is known to be highly anatomically variable in mice. Representative data show that using this alternative surgical approach decreases the variability in lesion volumes between the traditional MCAO approach and the alternative approach described here.

Intraluminal filament occlusion of the middle cerebral artery is the most frequently used in vivo model of experimental stroke in rodents. An alternative surgical approach to allow common carotid artery repair is performed here, which allows the reperfusion of the common carotid artery and a full reperfusion to the middle cerebral artery territory.

颅内动脉闭塞允许经普通颈动脉修复再灌注的研究

The ischemic stroke is a major cause of adult long-term disability and death worldwide. The current treatments available are limited, with only tissue ...

Two-vessel Occlusion Mouse Model of Cerebral Ischemia-reperfusion

In this study, a middle cerebral artery (MCA) occlusion mouse model is employed to study cerebral ischemia-reperfusion. A reproducible and reliable mouse model is useful for investigating the pathophysiology of cerebral ischemia-reperfusion and determining potential therapeutic strategies for patients with stroke. Variations in the anatomy of the circle of Willis of C57BL/6 mice affects their infarct volume after cerebral-ischemia-induced injury. Studies have indicated that distal MCA occlusion (MCAO) can overcome this problem and result in a stable infarct size. In this study, we establish a two-vessel occlusion mouse model of cerebral ischemia-reperfusion through the interruption of the blood flow to the right MCA. We distally ligate the right MCA and right common carotid artery (CCA) and restore blood flow after a certain period of ischemia. This ischemia-reperfusion injury induces an infarct of stable size and a behavioral deficit. Peripheral immune cells infiltrate the ischemic brain within the 24 h infiltration period. Additionally, the neuronal loss in the cortical area is less for a longer reperfusion duration. Therefore, this two-vessel occlusion model is suitable for investigating the immune response and neuronal recovery during the reperfusion period after cerebral ischemia.

A mouse model of cerebral ischemia-reperfusion is established to investigate the pathophysiology of stroke. We distally ligate the right middle cerebral artery and right common carotid artery and restore blood flow after 10 or 40 min of ischemia.

脑缺血再灌注的双血管闭塞小鼠模型

In this study, a middle cerebral artery (MCA) occlusion mouse model is employed to study cerebral ischemia-reperfusion. A reproducible and reliable mouse ...

Middle Cerebral Artery Occlusion in Rats with Preserved Vascular Anatomy

A Rat Model of Middle Cerebral Artery Occlusion/Reperfusion Without Damaging the Anatomical Structure of Cerebral Vessels

Ischemic stroke stands as the primary cause of long-term disability and mortality among adults worldwide. Animal models of ischemic stroke have significantly contributed to our understanding of its pathological mechanisms and the development of potential treatments. Presently, there are two common methods involving filament (endovascular suture) techniques to induce animal models of cerebral ischemia. However, these methods have inherent limitations, such as reduced blood perfusion to the brain, damage to the external carotid artery system, impaired food and/or water intake, and sensory dysfunction of the face. This article introduces a new method for inducing a rat ischemic stroke model without compromising the cerebral vascular anatomy. In this study, the common carotid artery (CCA) of Sprague-Dawley rats was exposed, and an incision was made. A filament was then inserted through the incision into the internal carotid artery to occlude the middle cerebral artery. After 1.5 h of induced ischemia, the occluding filament was fully removed from both the internal carotid artery and the CCA. The incision in the CCA was subsequently sutured using 11-0 microsurgical sutures under a microscope (magnification 4x). Through the utilization of microsurgical techniques to repair the CCA, this study successfully developed a unique method to induce an ischemic stroke model in rats while preserving the anatomical integrity of cerebral blood vessels.

The current protocol describes a rat model of middle cerebral artery occlusion/reperfusion that preserves the anatomical structure of cerebral vessels without causing damage.

Ischemic stroke stands as the primary cause of long-term disability and mortality among adults worldwide. Animal models of ischemic stroke have ...

神经科学

A Needle Model for Vascular Cognitive Impairment Studies in Mice

A Mouse Model for Vascular Cognitive Impairment and Dementia Based on Needle-guided Asymmetric Bilateral Common Carotid Artery Stenosis

Vascular cognitive impairment and dementia (VCID) results from vascular brain injury. Given VCID&#39;s high incidence, which is expected to continue rising as the population ages, it is critical to establish a robust animal model for the disease. This paper presents a novel method of creating a mouse model of VCID that is based on asymmetric bilateral common carotid artery stenosis, which mimics human chronic cerebral hypoperfusion caused by carotid atherosclerosis.
Briefly, common carotid arteries (CCAs) are ligated to different gauge needles (32 G for the right CCA and 34 G for the left CCA) using 7-0 silk sutures followed by immediate needle removal. The remaining suture rings cause persistent blood flow reduction and long-term cognitive impairment associated with white matter injury, microinfarcts, and reactive gliosis, thus closely mimicking the pathogenesis of VCID. Importantly, in this needle model, the clinical representations do not revert with time, providing reliable long-term cognitive impairment. Moreover, the survival rate 24 weeks post surgery was 81.6%, which is higher compared to the other established models of VCID with a similar level of blood flow reduction.
Additional advantages include low material cost and compatibility with MRI to monitor brain injury in live animals since no metal is implanted. The main challenge in employing the needle model of VCID is the requirement for developing advanced surgical skills since mouse CCAs are less than 0.6 mm in diameter and are very fragile. High-quality visual representation of the surgery will thus help researchers to master this technique and advance our understanding of VCID, potentially leading to the development of novel therapeutic modalities to decrease the devastating cognitive decline associated with VCID.

The needle method of asymmetric bilateral common carotid artery stenosis is proposed to create a mouse model for vascular cognitive impairment and dementia. It results in longer-term outcomes compared to previously established models and is compatible with live MRI. Visual representation demonstrating the procedure provides guidance for mastering the surgery.

Vascular cognitive impairment and dementia (VCID) results from vascular brain injury. Given VCID&#39;s high incidence, which is expected to continue ...

<meta charset="utf8"></head><body>用于研究视网膜病变的视网膜缺血再灌注损伤小鼠模型

Induction of Retinal Ischemia-Reperfusion Injury in a Mouse Eye Model

Ischemia-reperfusion injuries are known to cause a range of retinal pathologies, including diabetic retinopathy, glaucoma, retinal vascular occlusions, and other vaso-occlusive conditions. This manuscript presents a method for inducing ischemia-reperfusion injury in a mouse model. The method utilized anterior chamber cannulation attached to a saline reservoir, generating hydrostatic pressure to raise the intraocular pressure to 90-100 mmHg. This method effectively caused constriction of retinal capillaries to induce retinal ischemia. At the end of the ischemic period (60 min), the intraocular pressure was normalized (&#8804;20 mmHg) before removing the cannula from the anterior chamber to initiate reperfusion. Days after the ischemia/reperfusion procedure, the eyes were collected and sectioned for histological staining. The histopathology of the retinal sections was scored by evaluating eight parameters of retinal injury: folds, hemorrhage, deformation, cell loss in the ganglion cell, inner nuclear, outer nuclear, and photoreceptor layers, and damage to retinal pigment epithelial cells. This method provided a reproducible model to study the mechanisms and pathology of retinal ischemia/reperfusion injury. In addition, this model can facilitate the discovery of potential therapeutic targets to treat retinal ischemia/reperfusion injury, advancing the study of retinal pathologies and improving patient outcomes.

<meta charset="utf8"></head><body>小鼠眼模型中视网膜缺血再灌注损伤的诱导

This protocol models retinal ischemia-reperfusion injury in a mouse eye by inducing retinal ischemia via anterior chamber cannulation and intraocular pressure elevation, followed by intraocular pressure normalization to initiate the reperfusion.

小鼠眼模型中视网膜缺血再灌注损伤的诱导

Ischemia-reperfusion injuries are known to cause a range of retinal pathologies, including diabetic retinopathy, glaucoma, retinal vascular occlusions, ...