作者承认悉尼大学显微镜 &amp; 微量分析研究设施 (AMMRF) 和澳大利亚显微镜 &amp; 微微量分析中心 (ACMM) 的设施和科学和技术援助。这些研究得到了澳大利亚国家卫生和医学研究理事会 (澳洲) 项目赠款161558和 APP1124011 的支持。

所有动物伦理和议定书均经悉尼地方卫生区动物福利委员会和天津医科大学动物保育与使用委员会 (IACUC) 批准。所有实验都是根据悉尼大学和天津医科大学百年研究所的指导方针/条例进行的, 1。小鼠脑内海绵状畸形的诱导模型 <ol> <li> 跨 Cdh5-CreErt2;Ccm2 fl/fl 与 Ccm2 fl/fl 和 #160 的小鼠; 用 Cdh5-CreErt2 生成凋落物;Ccm2 fl/fl 和 #160;( Ccm2 iECKO ) pup 和 littermate 控件 ( Ccm2 fl/fl )。 Cdh5-CreErt2 和 Ccm2 fl/fl 动物先前被描述为 19 。
	<li> 在100% 乙醇中溶解 4HT, 存储在-80 和 #176; C 等分30和 #181; L (4HT 浓度:10 毫克/毫升)。在使用日, 稀释 aliquoted 4HT 的玉米油 (0.5 毫克/毫升). </li>
	<li> 灌注入50和 #181; L 4HT (0.5 毫克/毫升) 到 P1 的新生幼崽, 用胰岛素注射器诱导实验性 CCM 病变. </li>
</ol> 2。微 CT 扫描的样品制备 <ol> <li> 通过二氧化碳窒息在 P8 安乐新生幼崽. </li>
	<li> 通过在 PBS 中插入一个29口径的3毫升2% 甲醛的针头, 将10毫升注射器注入老鼠心脏的心室进行内灌注. 
	警告: 甲醛有毒;穿戴适当的保护. </li>
	<li> 使用剪刀将头部与身体分离。用剪刀把所有的皮肤从头上取下, 用钳子剥开头骨, 解剖整个大脑. </li>
	<li> 在7.82x 放大倍数、1x 增益、0.6 伽玛和20毫秒曝光时间内, 将大脑的图像显微镜. </li>
	<li> 在 PBS 解决方案中一夜之间修复4% 甲醛的解剖大脑. 
	警告: 甲醛有毒;穿戴适当的保护. </li>
	<li> 在第二天, 使用镊子分离 hindbrains, 并用 PBS 溶液冲洗. </li>
	<li> 在卢戈和 #39 的碘溶液中孵育 hindbrains 48 h. </li>
	<li> 在孵化后, 短暂风干 hindbrains 以去除过量的卢戈和 #39 的碘溶液. </li>
	<li> 将卢戈和 #39 的碘染 hindbrains 在0.65 毫升离心管和密封完全与塑料石蜡膜, 以避免组织萎缩 ( 图 2 A ). </li>
	<li> 将离心管放在5毫升塑料管中, 用海绵防止它们在扫描过程中移动 ( 图 2 B )。
</ol> 3。小鼠脑内 CCM 的显微 ct 扫描 <ol> <li> 垂直装入在微 ct 系统中的铝质支架上的管中的后脑. </li>
	<li> 将扫描参数设置为540投影和2的曝光时间, 其源条件为 50 kV 和 10 W, 以获取层析数据集 (图像分辨率9.5 和 #956; m/像素). </li>
	通过微 CT 系统提供的基于硬件的投影重建软件, 对扫描的 x 射线进行自动重建, 生成16位轴向切片 (#34、TXM 和 #34; 文件) 的图像序列. </li>
</ol> 4。微 CT 数据集分析 <ol> <li> 在3维分析软件中打开重建的图像文件 (#34; TXM 和 #34; 文件), 并使用和 #34 可视化大脑; 卷呈现和 #34; 函数. </li>
	<li> 将后脑转换为所需的方向, 方法是使用 #34; 边界框和 #34; #34; 修剪平面和 #34; 函数. </li>
	<li> 在扩展模式下对转换后的图像重新取样, 并保留体素大小. </li>
	<li> 创建和 #34; 编辑新标签字段和 #34; 在转换后的图像 (4.3) 上, 仅使用灰度强度突出显示后脑. </li>
	<li> 添加突出显示的区域和运行和 #34; 标签分析和 #34; 获取整个后脑的度量值 ( 即 、总体积和面积)。在 Excel 文件中导出度量值. </li>
	<li> 使用和 #34 显示后脑; 等值渲染和 #34; 函数. </li>
	<li> 创建其他 #34; 编辑新标签字段和 #34; 在变换后的图像上, 使用灰度强度突出病灶部位. </li>
	<li> 添加突出显示的区域和运行和 #34; 标签和 #34; 分析以获得后脑内病变的测量 (即: , 总体积和面积)。在 Excel 文件中导出度量值. </li>
	<li> 使用和 #34 可视化病灶; 生成表面和 #34; #34; 曲面视图和 #34; 函数. </li>
	<li> 按所需方向拍摄后脑的图像, 或为病灶的3维可视化生成电影. </li>
</ol>

<ol>
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作者没有什么可透露的。

CCM 是一种常见的血管畸形, 影响多达0.5% 的个人1。CCM 可以以零星或家族形式出现。患者的预后往往不清楚, 因为 CCM 病变可能破裂意外导致中风和其他神经后果。目前, 唯一的治疗方法是手术切除病灶, 伴随着高风险。
人类 CCM 条件最近被复制在动物模型7,8,9,10。?...

CCM 是薄壁, 扩张血管畸形在大脑中的流行率高达 0.5%, 在人口1。CCM 可以遗传为显性障碍, 由于功能突变的三基因之一: CCM1 (aka Krit1), CCM2, 和CCM3 (也称为PDCD10)2,3,4 ,5,6。这些基因存在于单一信号复合体中。
各种模型已经开发出模型人类 ccm 疾病和了解的 ccm 基因的下游途径, 负责 ccm7,8,9,10。最健壮的模型是有条件地删除任何一个Ccm基因与他莫昔芬诱导的Cdh5-CreERT2在 P1 在新生幼崽8,10。这些幼崽从 P6 发展到大脑中的 ccm 病变, 并有望成为临床前研究的理想模型, 以寻找治疗 ccm 疾病的机制和治疗剂。
在小鼠大脑中, CCM 病变的负担主要是用 histology-based 方法测量的, 这种方法非常耗时, 并受调查者的偏见10,11,12。采用 MRI 方法对成人小鼠模型9,13中的 CCM 损伤负荷进行评估。然而, 一个高度专业化的小动物磁共振成像仪和长时间扫描-一夜之间需要达到一个满意的分辨率, 以确定 CCM 病变。还有, MRI 是否可用于检测新生小鼠的 CCM 病变尚未报告, 分辨率可能会限制灵敏度。
我们最近开发了一种显微 CT 技术来图像和分析 CCM 病变14,15。这种高分辨率、时间和 cost-effective 的方法极大地提高了 CCM 疾病模型在机械和治疗研究中的价值。对比增强, 全贴装染色方法已用于软组织和小鼠胚胎的显微 CT 成像16,17。以前, 我们使用了 osmium-based 染色增强了在脑部14中 CCM 病变的微 CT 成像的对比度。本文采用了一种无毒、无损、低成本的试剂--碘基卢戈溶液, 增强了微 CT 成像的对比度。碘可以弥漫整个大脑和具有高亲和力的血液18。
详细的协议是在这里提出的诱导 ccm 病变的新生儿小鼠模型, 连同成像和分析的 ccm 病变的 contrast-based 微 CT。该方法对 ccm 病变体积进行了定量的全球测量, 准确地确定了小鼠脑内 ccm 病变的数目和3维位置, 大大降低了这些动物表型的成本和时间。

<table><tbody><tr><td>4-hydroxy tamoxifen</td><td>Sigma-Aldrich</td><td>H6278</td><td>To activate Cdh5-CreErt2</td></tr><tr><td>Corn oil</td><td>Sigma-Aldrich</td><td>C8267-500ML</td><td>To dilute 4-hydroxy tamoxifen</td></tr><tr><td>Stereomicroscope</td><td>Leica</td><td>M205FA</td><td>To take macroscopic images</td></tr><tr><td>Lugol&#039;s Iodine solution</td><td>Sigma-Aldrich</td><td>L6146</td><td>To stain samples for contrast micro-CT</td></tr><tr><td>Plastic paraffin film</td><td>Parafilm</td><td>PM992</td><td>To package samples</td></tr><tr><td>Micro-CT</td><td>Xradia</td><td>MicroXCT-400</td><td>Micro-CT</td></tr><tr><td>3D rendering software</td><td>FEI Visualization Science group</td><td>Avizo 3D image processing software</td><td>To analyse micro-CT scans</td></tr></tbody></table>

induction and micro-ct imaging of cerebral cavernous malformations in mouse model

突变在CCM1 (aka KRIT1), CCM2,或CCM3 (aka PDCD10)基因导致大脑海绵状畸形 (CCM) 在人类。在产后动物中, 用他莫昔芬引起的ccm基因缺失, 建立了小鼠 ccm 疾病模型。这些小鼠模型为研究 CCM 疾病的分子机制和治疗方法提供了宝贵的工具。准确和定量的方法来评估病变的负担和进展是必不可少的充分利用这些动物模型的价值。在这里, 我们演示了 ccm 疾病的诱导在一个小鼠模型和使用对比增强 X 射线显微计算机断层扫描 (微 CT) 方法测量 ccm 病变负荷的小鼠脑。在产后日 1 (P1), 我们使用 4-hydroxytamoxifen (4HT) 激活重组活动从 Cdh5-CreErt2 转基因, 以切割 floxed 等位基因的Ccm2。P8 对小鼠脑内 CCM 病变进行分析。在微 CT, 碘基卢戈的解决方案被用来提高对比度的脑组织。我们优化了扫描参数, 并利用了9.5 µm 的体素维数, 这导致了大约25µm 的最小特征尺寸。该分辨率足以全面准确地测量 ccm 病变体积和数量, 为小鼠脑内的 ccm 病变提供高质量的3维图谱。该方法提高了已建立的小鼠模型的价值, 研究了 CCM 和其他脑血管疾病的分子基础和潜在的疗法。

单注射4HT 在 P1 是足以诱发 CCM 病变的小脑。卢戈的碘对比微 CT 充分检测 CCM 病变, 并可以量化其体积和数量。利用优化的微 CT, 我们在Ccm2iECKO 小鼠的 hindbrains 中对 CCM 病变进行了成像。扫描的 X 射线图像重建, 以产生3维图像的鼠标的大脑, 这使得可视化整个病变的脑实质在不同的深度和方向, 和评估的结构和3的位置的病变在大脑中。重要的是, 这个图像数据?...

Watch this Scientific Journal Video about Induction and Micro-CT Imaging of Cerebral Cavernous Malformations in Mouse Model at JoVE.com

Induction and Micro-CT Imaging of Cerebral Cavernous Malformations in Mouse Model

本协议演示了在小鼠模型中诱导脑海绵状畸形的疾病, 并使用对比增强微计算机断层扫描来测量病变的负担。该方法提高了建立的小鼠模型的价值, 以研究脑海绵状畸形和其他血管性疾病的分子基础和潜在的疗法。

小鼠脑海绵体畸形的诱导及显微 CT 成像

Mutations in the CCM1 (aka KRIT1), CCM2, or CCM3 (aka PDCD10) gene cause cerebral cavernous malformation (CCM) in humans. Mouse models of CCM disease have ...

induction-micro-ct-imaging-cerebral-cavernous-malformations-mouse

Universidad de Cartagena UDEC

Research

JoVE Journal

Medicine

10.8K 次观看.  Centenary Institute. 本协议演示了在小鼠模型中诱导脑海绵状畸形的疾病, 并使用对比增强微计算机断层扫描来测量病变的负担。该方法提高了建立的小鼠模型的价值, 以研究脑海绵状畸形和其他血管性疾病的分子基础和潜在的疗法。

视频: Induction and Micro-CT Imaging of Cerebral Cavernous Malformations in Mouse Model

Cerebrovascular Casting of the Adult Mouse for 3D Imaging and Morphological Analysis

Vascular imaging is crucial in the clinical diagnosis and management of cerebrovascular diseases, such as brain arteriovenous malformations (BAVMs). Animal models are necessary for studying the etiopathology and potential therapies of cerebrovascular diseases. Imaging the vasculature in large animals is relatively easy. However, developing vessel imaging methods of murine brain disease models is desirable due to the cost and availability of genetically-modified mouse lines. Imaging the murine cerebral vascular tree is a challenge. In humans and larger animals, the gold standard for assessing the angioarchitecture at the macrovascular (conductance) level is x-ray catheter contrast-based angiography, a method not suited for small rodents.
In this article, we present a method of cerebrovascular casting that produces a durable skeleton of the entire vascular bed, including arteries, veins, and capillaries that may be analyzed using many different modalities. Complete casting of the microvessels of the mouse cerebrovasculature can be difficult; however, these challenges are addressed in this step-by-step protocol. Through intracardial perfusion of the vascular casting material, all vessels of the body are casted. The brain can then be removed and clarified using the organic solvent methyl salicylate. Three dimensional imaging of the brain blood vessels can be visualized simply and inexpensively with any conventional brightfield microscope or dissecting microscope. The casted cerebrovasculature can also be imaged and quantified using micro-computed tomography (micro-CT)1. In addition, after being imaged, the casted brain can be embedded in paraffin for histological analysis.
The benefit of this vascular casting method as compared to other techniques is its broad adaptation to various analytic tools, including brightfield microscopic analysis, CT scanning due to the radiopaque characteristic of the material, as well as histological and immunohistochemical analysis. This efficient use of tissue can save animal usage and reduce costs. We have recently demonstrated application of this method to visualize the irregular blood vessels in a mouse model of adult BAVM at a microscopic level2, and provide additional images of the malformed vessels imaged by micro-CT scan. Although this method has drawbacks and may not be ideal for all types of analyses, it is a simple, practical technique that can be easily learned and widely applied to vascular casting of blood vessels throughout the body.

In this article, we present a simple, practical technique for cerebrovascular casting that is easy to perform and can be utilized to image the vascular tree of the adult mouse brain.

成年鼠脑铸造三维成像和形态分析

Vascular imaging is crucial in the clinical diagnosis and management of cerebrovascular diseases, such as brain arteriovenous malformations (BAVMs). ...

科研

神经科学

Lateral Chronic Cranial Window Preparation Enables In Vivo Observation Following Distal Middle Cerebral Artery Occlusion in Mice

Focal cerebral ischemia (i.e., ischemic stroke) may cause major brain injury, leading to a severe loss of neuronal function and consequently to a host of motor and cognitive disabilities. Its high prevalence poses a serious health burden, as stroke is among the principal causes of long-term disability and death worldwide1. Recovery of neuronal function is, in most cases, only partial. So far, treatment options are very limited, in particular due to the narrow time window for thrombolysis2,3. Determining methods to accelerate recovery from stroke remains a prime medical goal; however, this has been hampered by insufficient mechanistic insights into the recovery process. Experimental stroke researchers frequently employ rodent models of focal cerebral ischemia. Beyond the acute phase, stroke research is increasingly focused on the sub-acute and chronic phase following cerebral ischemia. Most stroke researchers apply permanent or transient occlusion of the MCA in mice or rats. In patients, occlusions of the MCA are among the most frequent causes of ischemic stroke4. Besides proximal occlusion of the MCA using the filament model, surgical occlusion of the distal MCA is probably the most frequently used model in experimental stroke research5. Occlusion of a distal (to the branching of the lenticulo-striate arteries) MCA branch typically spares the striatum and primarily affects the neocortex. Vessel occlusion can be permanent or transient. High reproducibility of lesion volume and very low mortality rates with respect to the long-term outcome are the main advantages of this model. Here, we demonstrate how to perform a chronic cranial window (CW) preparation lateral to the sagittal sinus, and afterwards how to surgically induce a distal stroke underneath the window using a craniotomy approach. This approach can be applied for sequential imaging of acute and chronic changes following ischemia via epi-illuminating, confocal laser scanning, and two-photon intravital microscopy.

Lateral Chronic Cranial Window Preparation Enables In Vivo Observation Following Distal Middle Cerebral Artery Occlusion in Mice

Surgical occlusion of a distal middle cerebral artery branch (MCAo) is a frequently used model in experimental stroke research. This manuscript describes the basic technique of permanent MCAo, combined with the insertion of a lateral cranial window, which offers the opportunity for longitudinal intravital microscopy in mice.

横向慢性颅窗口准备启用<em&gt;在体内</em&gt;观察继末节小鼠大脑中动脉闭塞

Focal cerebral ischemia (i.e., ischemic stroke) may cause major brain injury, leading to a severe loss of neuronal function and consequently to a host of ...

Combined Near-infrared Fluorescent Imaging and Micro-computed Tomography for Directly Visualizing Cerebral Thromboemboli

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of stroke than relying on indirect measurements, and will be a potent and robust vascular research tool. We use an optical imaging approach that labels thrombi with a molecular imaging thrombus marker&#160;&#8212; a Cy5.5 near-infrared fluorescent (NIRF) probe that is covalently linked to the fibrin strands of the thrombus by the fibrin-crosslinking enzymatic action of activated coagulation factor XIIIa during the process of clot maturation. A micro-computed tomography (microCT)-based approach uses thrombus-seeking gold nanoparticles (AuNPs) functionalized to target the major component of the clot: fibrin. This paper describes a detailed protocol for the combined in vivo microCT and ex vivo NIRF imaging of thromboemboli in a mouse model of embolic stroke. We show that in vivo microCT and fibrin-targeted glycol-chitosan AuNPs (fib-GC-AuNPs) can be used for visualizing both in situ thrombi and cerebral embolic thrombi. We also describe the use of in vivo microCT-based direct thrombus imaging to serially monitor the therapeutic effects of tissue plasminogen activator-mediated thrombolysis. After the last imaging session, we demonstrate by ex vivo NIRF imaging the extent and the distribution of residual thromboemboli in the brain. Finally, we describe quantitative image analyses of microCT and NIRF imaging data. The combined technique of direct thrombus imaging allows two independent methods of thrombus visualization to be compared: the area of thrombus-related fluorescent signal on ex vivo NIRF imaging vs. the volume of hyperdense microCT thrombi in vivo.

This protocol describes the application of combined near-infrared fluorescent (NIRF) imaging and micro-computed tomography (microCT) for visualizing cerebral thromboemboli. This technique allows the quantification of thrombus burden and evolution. The NIRF imaging technique visualizes fluorescently labeled thrombus in excised brain, while the microCT technique visualizes thrombus inside living animals using gold-nanoparticles.

结合近红外荧光成像和微计算机断层扫描直接可视化脑血栓

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of ...

医学

Cannula Implantation into the Cisterna Magna of Rodents

Cisterna magna cannulation (CMc) is a straightforward procedure that enables direct access to the cerebrospinal fluid (CSF) without operative damage to the skull or the brain parenchyma. In anesthetized rodents, the exposure of the dura mater by blunt dissection of the neck muscles allows the insertion of a cannula into the cisterna magna (CM). The cannula, composed either by a fine beveled needle or borosilicate capillary, is attached via a polyethylene (PE) tube to a syringe. Using a syringe pump, molecules can then be injected at controlled rates directly into the CM, which is continuous with the subarachnoid space. From the subarachnoid space, we can trace CSF fluxes by convective flow into the perivascular space around penetrating arterioles, where solute exchange with the interstitial fluid (ISF) occurs. CMc can be performed for acute injections immediately following the surgery, or for chronic implantation, with later injection in anesthetized or awake, freely moving rodents. Quantitation of tracer distribution in the brain parenchyma can be performed by epifluorescence, 2-photon microscopy, and magnetic resonance imaging (MRI), depending on the physico-chemical properties of the injected molecules. Thus, CMc in conjunction with various imaging techniques offers a powerful tool for assessment of the glymphatic system and CSF dynamics and function. Furthermore, CMc can be utilized as a conduit for fast, brain-wide delivery of signaling molecules and metabolic substrates that could not otherwise cross the blood brain barrier (BBB).

Here we describe a protocol to perform cisterna magna cannulation (CMc), a minimally invasive way to deliver tracers, substrates and signaling molecules into the cerebrospinal fluid (CSF). Combined with different imaging modalities, CMc enables glymphatic system and CSF dynamics assessment, as well as brain-wide delivery of various compounds.

将套管植入啮齿动物的麦格纳池中

Cisterna magna cannulation (CMc) is a straightforward procedure that enables direct access to the cerebrospinal fluid (CSF) without operative damage to ...

A Volumetric Method for Quantification of Cerebral Vasospasm in a Murine Model of Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a subtype of hemorrhagic stroke. Cerebral vasospasm that occurs in the aftermath of the bleeding is an important factor determining patient outcome and is therefore frequently taken as a study endpoint. However, in small animal studies on SAH, quantification of cerebral vasospasm is a major challenge. Here, an ex vivo method is presented that allows quantification of volumes of entire vessel segments, which can be used as an objective measure to quantify cerebral vasospasm. In a first step, endovascular casting of the cerebral vasculature is performed using a radiopaque casting agent. Then, cross-sectional imaging data are acquired by micro computed tomography. The final step involves 3-dimensional reconstruction of the virtual vascular tree, followed by an algorithm to calculate center lines and volumes of the selected vessel segments. The method resulted in a highly accurate virtual reconstruction of the cerebrovascular tree shown by a diameter-based comparison of anatomical samples with their virtual reconstructions. Compared with vessel diameters alone, the vessel volumes highlight the differences between vasospastic and non-vasospastic vessels shown in a series of SAH and sham-operated mice.

The goal of this article is to present a method that allows a 3-dimensional reconstruction of the cerebrovascular tree in mice after micro computed tomography and determination of volumes of entire vessel segments that can be used to quantify cerebral vasospasm in murine models of subarachnoid hemorrhage.

小鼠蛛网膜下腔出血模型脑血管痉挛量化的容积法

Subarachnoid hemorrhage (SAH) is a subtype of hemorrhagic stroke. Cerebral vasospasm that occurs in the aftermath of the bleeding is an important factor ...

A Micro-CT-based Method for Characterizing Lesions and Locating Electrodes in Small Animal Brains

Lesion and electrode location verification are traditionally done via histological examination of stained brain slices, a time-consuming procedure that requires manual estimation. Here, we describe a simple, straightforward method for quantifying lesions and locating electrodes in the brain that is less laborious and yields more detailed results. Whole brains are stained with osmium tetroxide, embedded in resin, and imaged with a micro-CT scanner. The scans result in 3D digital volumes of the brains with resolutions and virtual section thicknesses dependent on the sample size (12&#8211;15 and 5&#8211;6 &#181;m&#160;per voxel for rat and zebra finch brains, respectively). Surface and deep lesions can be characterized, and single tetrodes, tetrode arrays, electrolytic lesions, and silicon probes can also be localized. Free and proprietary software allows experimenters to examine the sample volume from any plane and segment the volume manually or automatically. Because this method generates whole brain volume, lesions and electrodes can be quantified to a much higher degree than in current methods, which will help standardize comparisons within and across studies.

This article describes a straightforward method to prepare small animal brains for micro-CT imaging, in which lesions can be quantified and electrodes located with high precision in the context of the whole brain.

一种基于微 ct 的小动物脑损伤和定位电极表征方法

Lesion and electrode location verification are traditionally done via histological examination of stained brain slices, a time-consuming procedure that ...

Simultaneous Imaging of Microglial Dynamics and Neuronal Activity in Awake Mice

Since brain functions are under the continuous influence of the signals derived from peripheral tissues, it is critical to elucidate how glial cells in the brain sense various biological conditions in the periphery and transmit the signals to neurons. Microglia, immune cells in the brain, are involved in synaptic development and plasticity. Therefore, the contribution of microglia to neural circuit construction in response to the internal state of the body should be tested critically by intravital imaging of the relationship between microglial dynamics and neuronal activity.
Here, we describe a technique for the simultaneous imaging of microglial dynamics and neuronal activity in awake mice. Adeno-associated virus encoding R-CaMP, a gene-encoded calcium indicator of red fluorescence protein, was injected into layer 2/3 of the primary visual cortex in CX3CR1-EGFP transgenic mice expressing EGFP in microglia. After viral injection, a cranial window was installed onto the brain surface of the injected region. In vivo two-photon imaging in awake mice 4 weeks after the surgery demonstrated that neural activity and microglial dynamics could be recorded simultaneously at the sub-second temporal resolution. This technique can uncover the coordination between microglial dynamics and neuronal activity, with the former responding to peripheral immunological states and the latter encoding the internal brain states.

Here, we describe a protocol combining adeno-associated virus injection with cranial window implantation for simultaneous imaging of microglial dynamics and neuronal activity in awake mice.

清醒小鼠小胶质细胞动力学和神经元活动的同时成像

Since brain functions are under the continuous influence of the signals derived from peripheral tissues, it is critical to elucidate how glial cells in ...

建立经颅大脑中动脉闭塞小鼠模型

A Modified Transcranial Middle Cerebral Artery Occlusion Model to Study Stroke Outcomes in Aged Mice

In experimental stroke research, middle cerebral artery occlusion (MCAO) with an intraluminal filament is widely used to model ischemic stroke in mice. The filament MCAO model typically exhibits a massive cerebral infarction in C57Bl/6 mice that sometimes includes brain tissue in the territory supplied by the posterior cerebral artery, which is largely due to a high incidence of posterior communicating artery atresia. This phenomenon is considered a major contributor to the high mortality rate observed in C57Bl/6 mice during long-term stroke recovery after filament MCAO. Thus, many chronic stroke studies exploit distal MCAO models. However, these models usually produce infarction only in the cortex area, and consequently, the assessment of post-stroke neurologic deficits could be a challenge. This study has established a modified transcranial MCAO model in which the MCA at the trunk is partially occluded either permanently or transiently via a small cranial window. Since the occlusion location is relatively proximal to the origin of the MCA, this model generates brain damage in both the cortex and striatum. Extensive characterization of this model has demonstrated an excellent long-term survival rate, even in aged mice, as well as readily detectable neurologic deficits. Therefore, the MCAO mouse model described here represents a valuable tool for experimental stroke research.

作者聚焦:中风研究的创新技术和未来方向 

This protocol demonstrates a unique mouse stroke model with a medium-sized infarct and an excellent survival rate. This model allows preclinical stroke researchers to extend the ischemia duration, use aged mice, and assess long-term functional outcomes.

改进的经颅大脑中动脉闭塞模型研究老年小鼠脑卒中结局

In experimental stroke research, middle cerebral artery occlusion (MCAO) with an intraluminal filament is widely used to model ischemic stroke in mice. ...

小鼠脑海绵体畸形的诱导及显微 CT 成像

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此视频中的章节

成年鼠脑铸造三维成像和形态分析

横向慢性颅窗口准备启用

结合近红外荧光成像和微计算机断层扫描直接可视化脑血栓

将套管植入啮齿动物的麦格纳池中

小鼠蛛网膜下腔出血模型脑血管痉挛量化的容积法

一种基于微 ct 的小动物脑损伤和定位电极表征方法

清醒小鼠小胶质细胞动力学和神经元活动的同时成像

改进的经颅大脑中动脉闭塞模型研究老年小鼠脑卒中结局

改进的经颅大脑中动脉闭塞模型研究老年小鼠脑卒中结局

改进的经颅大脑中动脉闭塞模型研究老年小鼠脑卒中结局