本研究得到了国家自然科学基金第82102314号（至ZSJ）和32170977（至HSL）和广东省自然科学基金（编号:2022A1515010438（至ZSJ）和2022A1515012306（至HSL）的支持。本研究由暨南大学附属第一医院临床前沿技术项目支持，编号:JNU1AF-CFTP-2022-a01206（至HSL）。本研究得到了广州市科技计划项目 第202201020018号（至HSL）、2023A04J1284（至ZSJ）和2023A03J1024（至HSL）的支持。

涉及动物的研究由暨南大学伦理委员会审查和批准。
1.动物麻醉和T10椎板切除术
<ol><li>使用 8 周龄的雌性年轻成年 C57/6J 小鼠进行本研究。通过腹膜内注射氯胺酮（100mg / kg）和地西泮（5mg / kg）麻醉小鼠。检查麻醉是否成功，表现为疼痛反射丧失。在眼睛上涂抹兽医软膏，以防止麻醉下干燥。</li>
	<li>用剃须刀剃掉老鼠背部的毛发，露出皮肤。用三轮碘磷和酒精交替消毒皮肤。</li>
	<li>用手术刀在背侧皮肤上做 2.5 厘米的内侧纵向切口，并使用镊子在 T9-T11 水平暴露脊柱。</li>
	<li>使用脊柱固定器双侧固定 T10 小关节。确保脊柱稳定固定。确保剥离椎旁肌肉，并使用微磨钻去除棘突和椎板，以暴露 T10 节段的脊髓。</li>
</ol>2. 使用 G smart SCI 系统对 T10 脊髓进行挫伤
<ol><li>打开开关，等待设备自动恢复到原始状态。将脊柱固定器放入 G smart SCI 系统中，并用螺钉固定。</li>
	<li>使用操作触摸屏（图2A），设置损伤参数，包括冲击速度（1 m / s），冲击深度（三组不同的小鼠为0.5 mm，0.8 mm和1.1 mm）和停留时间（500 ms）15。</li>
	<li>通过移动平台将激光测距仪对准暴露的脊髓中心。（图2B）</li>
	<li>单击触摸屏上的 Ready 按钮（图 2C）。冲击头将根据设置参数自动调整到特定高度。托架台自动将脊髓撞击部位移动到撞击头下方。</li>
	<li>手动按压冲击头以进一步确定冲击部位。单击 "开始 "按钮，冲击头将根据设置的参数撞击脊髓。</li>
	<li>将小鼠从设备中取出并在体视显微镜（20x）下观察以确定脊髓损伤（图3）。为了确定模型开发是否成功，请观察局部充血、塌陷和脊髓膜破裂。</li>
	<li>使用 3-0 缝合线逐层缝合肌肉、筋膜和皮肤。将小鼠放入温暖的盒子中，等待它们恢复。</li>
</ol>3. 术后护理
<ol><li>手术后每天皮下注射美洛昔康（5mg/kg），持续 7 天。每8小时手动排空膀胱，直到膀胱功能恢复。</li>
	<li>手术后 14 天，移除缝合线。</li>
</ol>4. 脊髓损伤的检测效果
<ol><li>从术后第一天开始计算小鼠的BMS评分16,17。</li>
	<li>术后第30天，进行动物行为实验，包括走秀、足部断层和旋转16,17。走秀:创纪录的45厘米距离;最大运行持续时间 8 秒;相机增益:28.02;强度阈值 0.01。脚故障:为每只鼠标记录 60 步。旋转杆:速度 20 rpm。记录鼠标下落的时间，并记录为 120 秒以上 120 秒。</li>
	<li>术后第31天，腹膜内注射氯胺酮（100mg/kg）和地西泮（5mg/kg）麻醉小鼠，然后用4%PFA灌注对小鼠实施安乐死。小心地取出脊髓，并在受伤部位上方和下方截取 5 毫米以进行石蜡包埋。在小鼠脊髓损伤中心做一个5μm的切片，并进行苏木精和伊红染色17。</li>
	<li>对于统计分析，请使用商业软件。将数据表示为均值±均值标准误差 （SEM），并使用单因素方差分析进行比较;p < 0.05 被认为是显著的。</li>
</ol>

用于精确小鼠模型的脊髓损伤挫伤装置

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作者声明没有相互竞争的经济利益。

脊髓损伤可导致感觉和运动缺陷，从而导致严重的身体和精神损伤。在中国，不同省份的脊髓损伤发病率从14.6/100万到60.6不等18。脊髓损伤患病率的增加将给医疗保健系统带来更大的压力。目前，脊髓损伤的有效治疗选择有限，因为其病理机制和修复过程尚未完全了解19。有必要创建准确且可重复的脊髓损伤动物模型，以研究脊髓损伤的病理机制和修复过程。为...

脊髓损伤通常会导致损伤节段以下的永久性脊髓功能障碍。它多是由物体撞击脊柱和脊柱过度伸展引起的，例如交通事故和跌倒1.由于脊髓损伤的有效治疗方案有限，使用动物模型阐明脊髓损伤的发病机制将有助于制定适当的治疗方法。由脊髓撞击引起的脊髓损伤挫伤模型导致开发了与大多数临床脊髓损伤病例具有相似病理的动物模型 2,3。因此，为脊髓损伤挫伤生成准确、可重复和方便的动物模型非常重要。
自 Allen 于 1911 年发明第一个脊髓损伤动物模型以来，用于建立脊髓损伤动物模型的仪器的发展取得了重大进展 4,5。根据损伤机制，脊髓损伤模型分为挫伤、压迫、牵引、脱位、横断或化学6。其中，利用外力移位和损伤脊髓的挫伤模型最接近大多数脊髓损伤患者的临床病因。因此，挫伤模型已被许多研究人员用于脊髓损伤研究 3,7。各种仪器用于开发脊髓损伤挫伤模型。纽约大学 （NYU） 多中心动物脊髓损伤研究 （MASCIS） 撞击器通过减重装置产生脊髓损伤挫伤8.经过几个更新版本后，MASCIS撞击器被广泛用于开发脊髓损伤挫伤动物模型9。然而，当MASCIS的冲击杆掉落并撞击脊髓时，可能会发生多处损伤，这会影响脊髓损伤模型的损伤程度。此外，实现机械精度以确保仪器的精度和制造模型的可重复性也具有挑战性。无限地平线撞击器通过控制施加在脊髓上的力而不是重跌落来引起挫伤10.它使用连接到传感器的计算机直接测量撞击器和脊髓之间的冲击力。当达到阈值时，冲击器立即缩回，从而避免重量反弹并提高精度10,11。然而，使用这种精细运动方式造成损伤会导致不一致的损伤和功能缺陷6.俄亥俄州立大学（OSU）设备通过电磁驱动器12,13以瞬态速率压缩脊髓的背面。该装置类似于无限地平线撞击器，因为它使用短距离按压来引起脊髓损伤。然而，它有各种局限性，因为零点的初始确定会由于脑脊液的存在而引起误差6,14。综上所述，可用于开发脊髓损伤挫伤动物模型的仪器很多，但它们都存在一些局限性，导致动物模型的准确性和可重复性不足。因此，为了更准确、更方便、更可重复地创建脊髓损伤小鼠挫伤模型，需要一种自动化、智能化的脊髓损伤撞击器。
我们提出了一种新型的脊髓损伤冲击器，广州暨南大学智能脊髓损伤系统（G smart SCI system; 图1），用于生成脊髓损伤挫伤模型。该设备使用激光测距仪作为定位装置，结合自动化移动平台，根据设定的打击参数（包括打击速度、打击深度和停留时间）自动进行打击。自动化操作减少了人为因素，提高了动物模型的准确性和可重复性。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.01M PBS (powder, pH7.2-7.4)</td>
			<td>Solarbio Life Sciences</td>
			<td>P1010</td>
			<td></td>
		</tr>
		<tr>
			<td>2,2,2-Tribromoethanol</td>
			<td>Macklin</td>
			<td>75-80-9</td>
			<td></td>
		</tr>
		<tr>
			<td>4% paraformaldehyde tissue fixative</td>
			<td>Biosharp life science</td>
			<td>BL539A</td>
			<td></td>
		</tr>
		<tr>
			<td>Biomicroscope</td>
			<td>Leica</td>
			<td>LCC50 HD</td>
			<td></td>
		</tr>
		<tr>
			<td>CatWalk&#160;</td>
			<td>Noldus Information Technology</td>
			<td>CatWalk XT 9.1</td>
			<td></td>
		</tr>
		<tr>
			<td>Cover glass</td>
			<td>CITOTEST Scientific</td>
			<td>10212432C</td>
			<td></td>
		</tr>
		<tr>
			<td>Embedding machine</td>
			<td>Changzhou Zhongwei Electronic Instrument</td>
			<td>BMJ-A</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol absolute</td>
			<td>DAMAO</td>
			<td>64-17-5</td>
			<td></td>
		</tr>
		<tr>
			<td>FootFaultScan</td>
			<td>Clever Sys Inc.</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass slide</td>
			<td>CITOTEST Scientific</td>
			<td>80302-2104</td>
			<td></td>
		</tr>
		<tr>
			<td>Hematoxylin and Eosin Staining Kit</td>
			<td>Beyotime Biotechnology</td>
			<td>C0105S</td>
			<td></td>
		</tr>
		<tr>
			<td>micro-grinding drill&#160;</td>
			<td>FEIYUBIO</td>
			<td>19-7010</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse spinal fixator</td>
			<td>RWD Life Science</td>
			<td>68094</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraffin microtome</td>
			<td>Thermo</td>
			<td>shandon finesse 325</td>
			<td></td>
		</tr>
		<tr>
			<td>RotaRod for Mice</td>
			<td>Ugo Basile</td>
			<td>47600</td>
			<td></td>
		</tr>
		<tr>
			<td>Stereomicroscope</td>
			<td>KUY NICE</td>
			<td>SZM-7045</td>
			<td></td>
		</tr>
		<tr>
			<td>Tert-Amyl alcohol</td>
			<td>Macklin</td>
			<td>75-85-4</td>
			<td></td>
		</tr>
		<tr>
			<td>Xylene</td>
			<td>China National Pharmaceutical</td>
			<td>#10023418</td>
			<td></td>
		</tr>
	</tbody>
</table>

automated impactor for contusive spinal cord injury model in mice

由车祸和跌倒等创伤引起的脊髓损伤 （SCI） 与永久性脊髓功能障碍有关。通过撞击脊髓来创建脊髓损伤的挫伤模型会导致与临床实践中大多数脊髓损伤相似的病理。准确、可重复和方便的脊髓损伤动物模型对于研究脊髓损伤至关重要。我们提出了一种新型的小鼠自动脊髓损伤挫伤装置，即广州暨南大学智能脊髓损伤系统，该系统可以生成具有准确性、可重复性和便利性的脊髓损伤挫伤模型。该系统 通过 激光距离传感器与自动化移动平台和高级软件相结合，精确地生成不同程度的脊髓损伤模型。我们使用该系统创建了三个级别的脊髓损伤小鼠模型，确定了它们的 Basso 小鼠量表 （BMS） 评分，并进行了行为和染色测定以证明其准确性和可重复性。我们展示了使用该设备开发损伤模型的每个步骤，形成了一个标准化的程序。该方法可产生可重复的脊髓损伤挫伤小鼠模型，并通过方便的处理程序减少人为操作因素。开发的动物模型对于研究脊髓损伤机制和相关治疗方法是可靠的。

如上所述，对 24 只雌性小鼠（8 周龄）进行椎板切除术。假手术组（n=6）小鼠未发生脊髓损伤，其余小鼠，包括0.5 mm组（n=6）、0.8 mm组（n=6）和1.1 mm组（n=6）均受到不同深度的脊髓撞击。定期记录 BMS 评分，直至术后 1 个月（图 4）。不同组小鼠术后BMS评分差异有统计学意义。1个月后，0.5mm组小鼠术后评分为4-6分，恢复到与假手术组相似的水平。0.8 mm 和 1.1 mm 组的小鼠术后评...

Watch this Scientific Journal Video about Automated Impactor for Contusive Spinal Cord Injury Model in Mice at JoVE.com

作者聚焦:深入了解脊髓损伤研究的创新

这里介绍的是一种新型的小鼠自动脊髓损伤挫伤装置，可以准确生成不同程度的脊髓损伤挫伤模型。

用于小鼠挫伤脊髓损伤模型的自动撞击器

Spinal cord injury (SCI) due to traumatic injuries such as car accidents and falls is associated with permanent spinal cord dysfunction. Creation of ...

我的研究范围包括脊髓损伤的发病机制和治疗方法。我们最近的研究发现，各种生物材料可以通过抗氧化应激促进小鼠脊髓损伤的修复。生物材料传感器、技术和基因修饰技术的发展，以及脊髓损伤模型的优化正在推进我们的研究领域。由于脊髓损伤的压迫和机制不完全了解，目前很难使用单一干预措施来治愈脊髓损伤。未来，研究可能需要多种干预方法。我们发现精神即刻敷可以通过抗氧化应激参与动物脊髓损伤的治疗和修复。

automated-impactor-for-contusive-spinal-cord-injury-model-in-mice

Research

JoVE Journal

Neuroscience

Automated Impactor for Contusive Spinal Cord Injury Model in Mice

1.6K 次观看.  Jinan University. 我的研究范围包括脊髓损伤的发病机制和治疗方法。我们最近的研究发现，各种生物材料可以通过抗氧化应激促进小鼠脊髓损伤的修复。生物材料传感器、技术和基因修饰技术的发展，以及脊髓损伤模型的优化正在推进我们的研究领域。由于脊髓损伤的压迫和机制不完全了解，目前很难使用单一干预措施来治愈脊髓损伤。未来，研究可能需要多种干预方法。我们发现精?...

视频: 作者聚焦:深入了解脊髓损伤研究的创新

Lateral Fluid Percussion: Model of Traumatic Brain Injury in Mice

Traumatic brain injury (TBI) research has attained renewed momentum due to the increasing awareness of head injuries, which result in morbidity and mortality. Based on the nature of primary injury following TBI, complex and heterogeneous secondary consequences result, which are followed by regenerative processes 1,2. Primary injury can be induced by a direct contusion to the brain from skull fracture or from shearing and stretching of tissue causing displacement of brain due to movement 3,4. The resulting hematomas and lacerations cause a vascular response 3,5, and the morphological and functional damage of the white matter leads to diffuse axonal injury 6-8. Additional secondary changes commonly seen in the brain are edema and increased intracranial pressure 9. Following TBI there are microscopic alterations in biochemical and physiological pathways involving the release of excitotoxic neurotransmitters, immune mediators and oxygen radicals 10-12, which ultimately result in long-term neurological disabilities 13,14. Thus choosing appropriate animal models of TBI that present similar cellular and molecular events in human and rodent TBI is critical for studying the mechanisms underlying injury and repair.
Various experimental models of TBI have been developed to reproduce aspects of TBI observed in humans, among them three specific models are widely adapted for rodents: fluid percussion, cortical impact and weight drop/impact acceleration 1. The fluid percussion device produces an injury through a craniectomy by applying a brief fluid pressure pulse on to the intact dura. The pulse is created by a pendulum striking the piston of a reservoir of fluid. The percussion produces brief displacement and deformation of neural tissue 1,15. Conversely, cortical impact injury delivers mechanical energy to the intact dura via a rigid impactor under pneumatic pressure 16,17. The weight drop/impact model is characterized by the fall of a rod with a specific mass on the closed skull 18. Among the TBI models, LFP is the most established and commonly used model to evaluate mixed focal and diffuse brain injury 19. It is reproducible and is standardized to allow for the manipulation of injury parameters. LFP recapitulates injuries observed in humans, thus rendering it clinically relevant, and allows for exploration of novel therapeutics for clinical translation 20.
We describe the detailed protocol to perform LFP procedure in mice. The injury inflicted is mild to moderate, with brain regions such as cortex, hippocampus and corpus callosum being most vulnerable. Hippocampal and motor learning tasks are explored following LFP.

Lateral fluid percussion (LFP), an established model of traumatic brain injury in mice, is demonstrated. LFP fulfills three major criteria for animal models: validity, reliability and clinical relevance. The procedure, consisting of surgical craniotomy, fixation of hub followed by induction of injury, resulting in focal and diffuse injuries, is described.

侧向液压冲击:创伤性脑损伤小鼠模型

Traumatic brain injury (TBI) research has attained renewed momentum due to the increasing awareness of head injuries, which result in morbidity and ...

科研

神经科学

An Ex Vivo Laser-induced Spinal Cord Injury Model to Assess Mechanisms of Axonal Degeneration in Real-time

Injured CNS axons fail to regenerate and often retract away from the injury site. Axons spared from the initial injury may later undergo secondary axonal degeneration. Lack of growth cone formation, regeneration, and loss of additional myelinated axonal projections within the spinal cord greatly limits neurological recovery following injury. To assess how central myelinated axons of the spinal cord respond to injury, we developed an ex vivo living spinal cord model utilizing transgenic mice that express yellow fluorescent protein in axons and a focal and highly reproducible laser-induced spinal cord injury to document the fate of axons and myelin (lipophilic fluorescent dye Nile Red) over time using two-photon excitation time-lapse microscopy. Dynamic processes such as acute axonal injury, axonal retraction, and myelin degeneration are best studied in real-time. However, the non-focal nature of contusion-based injuries and movement artifacts encountered during in vivo spinal cord imaging make differentiating primary and secondary axonal injury responses using high resolution microscopy challenging. The ex vivo spinal cord model described here mimics several aspects of clinically relevant contusion/compression-induced axonal pathologies including axonal swelling, spheroid formation, axonal transection, and peri-axonal swelling providing a useful model to study these dynamic processes in real-time. Major advantages of this model are excellent spatiotemporal resolution that allows differentiation between the primary insult that directly injures axons and secondary injury mechanisms; controlled infusion of reagents directly to the perfusate bathing the cord; precise alterations of the environmental milieu (e.g., calcium, sodium ions, known contributors to axonal injury, but near impossible to manipulate in vivo); and murine models also offer an advantage as they provide an opportunity to visualize and manipulate genetically identified cell populations and subcellular structures. Here, we describe how to isolate and image the living spinal cord from mice to capture dynamics of acute axonal injury.

An Ex Vivo Laser-induced Spinal Cord Injury Model to Assess Mechanisms of Axonal Degeneration in Real-time

We present a protocol utilizing two-photon excitation time-lapse microscopy to simultaneously visualize the dynamics of axon and myelin injuries in real time. This proposed protocol permits studies of both intrinsic and extrinsic factors which can influence central myelinated axon fate after injury and contribute to permanent clinical disability.

一个<em&gt;离体</em&gt;激光诱导脊髓损伤模型，以评估轴索变性的机制在实时

Injured CNS axons fail to regenerate and often retract away from the injury site. Axons spared from the initial injury may later undergo secondary axonal ...

Imaging Neural Activity in the Primary Somatosensory Cortex Using Thy1-GCaMP6s Transgenic Mice

The mammalian brain exhibits marked symmetry across the sagittal plane. However, detailed description of neural dynamics in symmetric brain regions in adult mammalian animals remains elusive. In this study, we describe an experimental procedure for measuring calcium dynamics through dual optical windows above bilateral primary somatosensory corticies (S1) in Thy1-GCaMP6s transgenic mice using 2-photon (2P) microscopy. This method enables recordings and quantifications of neural activity in bilateral mouse brain regions one at a time in the same experiment for a prolonged period in vivo. Key aspects of this method, which can be completed within an hour, include minimally invasive surgery procedures for creating dual optical windows, and the use of 2P imaging. Although we only demonstrate the technique in the S1 area, the method can be applied to other regions of the living brain facilitating the elucidation of structural and functional complexities of brain neural networks.

Imaging Neural Activity in the Primary Somatosensory Cortex Using Thy1-GCaMP6s Transgenic Mice

We describe an experimental procedure for measuring neuronal activity through dual optical windows above bilateral primary somatosensory corticies (S1) in Thy1-GCaMP6s transgenic mice using 2-photon (2P) microscopy in vivo.

胸腺1-gmcmp6 转基因小鼠在原代体血源皮质中的成像神经活性

The mammalian brain exhibits marked symmetry across the sagittal plane. However, detailed description of neural dynamics in symmetric brain regions in ...

An In Vivo Duo-color Method for Imaging Vascular Dynamics Following Contusive Spinal Cord Injury

Spinal cord injury (SCI) causes significant vascular disruption at the site of injury. Vascular pathology occurs immediately after SCI and continues throughout the acute injury phase. In fact, endothelial cells appear to be the first to die after a contusive SCI. The early vascular events, including increased permeability of the blood-spinal cord barrier (BSCB), induce vasogenic edema and contribute to detrimental secondary injury events caused by complex injury mechanisms. Targeting the vascular disruption, therefore, could be a key strategy to reduce secondary injury cascades that contribute to histological and functional impairments after SCI. Previous studies were mostly performed on postmortem samples and were unable to capture the dynamic changes of the vascular network. In this study, we have developed an in vivo duo-color two-photon imaging method to monitor acute vascular dynamic changes following contusive SCI. This approach allows detecting blood flow, vessel diameter, and other vascular pathologies at various sites of the same rat pre- and post-injury. Overall, this method provides an excellent venue for investigating vascular dynamics.

An In Vivo Duo-color Method for Imaging Vascular Dynamics Following Contusive Spinal Cord Injury

We introduce an in vivo imaging method using two different fluorescent dyes to track dynamic spinal vascular changes following a contusive spinal cord injury in adult Sprague-Dawley rats.

在体内挫伤脊髓损伤后影像血管动力学的双色法

Spinal cord injury (SCI) causes significant vascular disruption at the site of injury. Vascular pathology occurs immediately after SCI and continues ...

Activity-based Training on a Treadmill with Spinal Cord Injured Wistar Rats

Spinal cord injury (SCI) results in lasting deficits that include both mobility and a multitude of autonomic-related dysfunctions. Locomotor training (LT) on a treadmill is widely used as a rehabilitation tool in the SCI population with many benefits and improvements to daily life. We utilize this method of activity-based task-specific training (ABT) in rodents after SCI to both elucidate the mechanisms behind such improvements and to enhance and improve upon existing clinical rehabilitation protocols. Our current goal is to determine the mechanisms underlying ABT-induced improvements in urinary, bowel, and sexual function in SCI rats after a moderate to severe level of contusion. After securing each individual animal in a custom-made adjustable vest, they are secured to a versatile body weight support mechanism, lowered to a modified three-lane treadmill and assisted in step-training for 58 minutes, once a day for 10 weeks. This setup allows for the training of both quadrupedal and forelimb-only animals, alongside two different non-trained groups. Quadrupedal-trained animals with body weight support are aided by a technician present to assist in stepping with proper hind limb placement as necessary, while forelimb-only trained animals are raised at the caudal end to ensure no hind limb contact with the treadmill and no weight-bearing. One non-trained SCI group of animals is placed in a harness and rests next to the treadmill, while the other control SCI group remains in its home cage in the training room nearby. This paradigm allows for the training of multiple SCI animals at once, thus making it more time-efficient in addition to ensuring that our pre-clinical animal model mimics the clinical representation as close as possible, particularly with respect to the body weight support with manual assistance.

This protocol demonstrates our model of activity-based locomotor treadmill training for rats with spinal cord injury (SCI). Included is both quadrupedal and forelimb-only groups, in addition to two distinct types of non-trained control groups. Investigators are able to assess training effects on SCI rats using this protocol.

脊髓损伤 wistar 大鼠跑步机的作业训练

Spinal cord injury (SCI) results in lasting deficits that include both mobility and a multitude of autonomic-related dysfunctions. Locomotor training (LT) ...

Intra-Arterial Delivery of Neural Stem Cells to the Rat and Mouse Brain: Application to Cerebral Ischemia

Neural stem cell (NSC) therapy is an emerging innovative treatment for stroke, traumatic brain injury and neurodegenerative disorders. As compared to intracranial delivery, intra-arterial administration of NSCs is less invasive and produces a more diffuse distribution of NSCs within the brain parenchyma. Further, intra-arterial delivery allows the first-pass effect in the brain circulation, lessening the potential for trapping of cells in peripheral organs, such as liver and spleen, a complication associated with peripheral injections. Here, we detail the methodology, in both mice and rats, for delivery of NSCs through the common carotid artery (mouse) or external carotid artery (rat) to the ipsilateral hemisphere after an ischemic stroke. Using GFP-labeled NSCs, we illustrate the widespread distribution achieved throughout the rodent ipsilateral hemisphere at 1 d, 1 week and 4 weeks after postischemic delivery, with a higher density in or near the ischemic injury site. In addition to long-term survival, we show evidence of differentiation of GFP-labeled cells at 4 weeks. The intra-arterial delivery approach described here for NSCs can also be used for administration of therapeutic compounds, and thus has broad applicability to varied CNS injury and disease models across multiple species.

A method for delivering neural stem cells, adaptable for injecting solutions or suspensions, through the common carotid artery (mouse) or external carotid artery (rat) after ischemic stroke is reported. Injected cells are distributed broadly throughout the brain parenchyma and can be detected up to 30 d after delivery.

神经干细胞向大鼠和小鼠大脑的动脉内传递:对脑缺血的应用

Neural stem cell (NSC) therapy is an emerging innovative treatment for stroke, traumatic brain injury and neurodegenerative disorders. As compared to ...

Induction of Complete Transection-Type Spinal Cord Injury in Mice

Spinal cord injury (SCI) largely leads to irreversible and permanent loss of function, most commonly as a result of trauma. Several treatment options, such as cell transplantation methods, are being researched to overcome the debilitating disabilities arising from SCI. Most pre-clinical animal trials are conducted in rodent models of SCI. While rat models of SCI have been widely used, mouse models have received less attention, even though mouse models can have significant advantages over rat models. The small size of mice equates to lower animal maintenance costs than for rats, and the availability of numerous transgenic mouse models is advantageous for many types of studies. Inducing repeatable and precise injury in the animals is the primary challenge for SCI research, which in small rodents requires high-precision surgery. The transection-type injury model has been a commonly used injury model over the last decade for transplantation-based therapeutic research, however a standardized method for inducing a complete transection-type injury in mice does not exist. We have developed a surgical protocol for inducing a complete transection type injury in C57BL/6 mice at thoracic vertebral level 10 (T10). The procedure uses a small tip drill instead of rongeurs to precisely remove the lamina, after which a thin blade with rounded cutting edge is used to induce the spinal cord transection. This method leads to reproducible transection-type injury in small rodents with minimal collateral muscle and bone damage and therefore minimizes confounding factors, specifically where behavioral functional outcomes are analyzed.

This protocol describes how to create a precise laminectomy for induction of stable transection-type spinal cord injury in the mouse model, with minimal collateral damage for spinal cord injury research.

小鼠完全转型脊髓损伤的诱导

Spinal cord injury (SCI) largely leads to irreversible and permanent loss of function, most commonly as a result of trauma. Several treatment options, ...

Automated Gait Analysis to Assess Functional Recovery in Rodents with Peripheral Nerve or Spinal Cord Contusion Injury

Peripheral and central nerve injuries are mostly studied in rodents, especially rats, given the fact that these animal models are both cost-effective and a lot of comparative data has been published in the literature. This includes a multitude of assessment methods to study functional recovery following nerve injury and repair. Besides evaluation of nerve regeneration by means of histology, electrophysiology, and other in vivo and in vitro assessment techniques, functional recovery is the most important criterion to determine the degree of neural regeneration. Automated gait analysis allows recording of a vast quantity of gait-related parameters such as Paw Print Area and Paw Swing Speed as well as measures of inter-limb coordination. Additionally, the method provides digital data of the rats&#8217; paws after neuronal damage and during nerve regeneration, adding to our understanding of how peripheral and central nervous injuries affect their locomotor behavior. Besides the predominantly used sciatic nerve injury model, other models of peripheral nerve injury such as the femoral nerve can be studied by means of this method. In addition to injuries of the peripheral nervous systems, lesions of the central nervous system, e.g., spinal cord contusion can be evaluated. Valid and reproducible data assessment is strongly dependent on meticulous adjustment of the hard- and software settings prior to data acquisition. Additionally, proper training of the experimental animals is of crucial importance. This work aims to illustrate the use of computerized automated gait analysis to assess functional recovery in different animal models of peripheral nerve injury as well as spinal cord contusion injury. It also emphasizes the method&#8217;s limitations, e.g., evaluation of nerve regeneration in rats with sciatic nerve neurotmesis due to limited functional recovery. Therefore, this protocol is thought to help researchers interested in peripheral and central nervous injuries to assess functional recovery in rodent models.

Automated gait analysis is a feasible tool to evaluate functional recovery in rodent models of peripheral nerve injury and spinal cord contusion injury. While it requires only one setup to assess locomotor function in various experimental models, meticulous hard- and soft-ware adjustment and training of the animals is highly important.

自动步态分析，评估带外周神经或脊髓挫伤的啮齿动物的功能恢复

Peripheral and central nerve injuries are mostly studied in rodents, especially rats, given the fact that these animal models are both cost-effective and ...

Establishing a Mouse Contusion Spinal Cord Injury Model Based on a Minimally Invasive Technique

Using minimally invasive methods to model spinal cord injury (SCI) can minimize behavioral and histological differences between experimental animals, thereby improving the reproducibility of the experiments.
These methods need two requirements to be fulfilled: clarity of the surgical anatomical pathway and simplicity and convenience of the laboratory device. Crucially for the operator, a clear anatomical pathway provides minimally invasive exposure, which avoids additional damage to the experimental animal during the surgical procedures and allows the animal to maintain a consistent and stable anatomical morphology during the experiment.
In this study, the use of a novel integrated platform called the SCI coaxial platform for spinal cord injury in small animals to expose the T9 level spinal cord in a minimally invasive way and stabilize and immobilize the vertebra of mice using a vertebral stabilizer is researched, and, finally, a coaxial gravity impactor is used to contuse the spinal cord of mice to approach different degrees of T9 spinal cord injury. Finally, histological results are provided as a reference for the readers.

Minimally invasive techniques and a simple laboratory device improve the reproducibility of the spinal cord injury model by reducing operative damage to the experimental animals and allowing anatomical morphology maintenance. The method is worthwhile because the reliable results and reproducible procedure facilitate investigations of the mechanisms of disease reparation.

基于微创技术的小鼠挫伤脊髓损伤模型的建立

Using minimally invasive methods to model spinal cord injury (SCI) can minimize behavioral and histological differences between experimental animals, ...

Electromagnetic Controlled Closed-Head Model of Mild Traumatic Brain Injury in Mice

Highly reproducible animal models of traumatic brain injury (TBI), with well-defined pathologies, are needed for testing therapeutic interventions and understanding the mechanisms of how a TBI alters brain function. The availability of multiple animal models of TBI is necessary to model the different aspects and severities of TBI seen in people. This manuscript describes the use of a midline closed head injury (CHI) to develop a mouse model of mild TBI. The model is considered mild because it does not produce structural brain lesions based on neuroimaging or gross neuronal loss. However, a single impact creates enough pathology that cognitive impairment is measurable at least 1 month after injury. A step-by-step protocol to induce a CHI in mice using a stereotaxically guided electromagnetic impactor is defined in the paper. The benefits of the mild midline CHI model include the reproducibility of the injury-induced changes with low mortality. The model has been temporally characterized up to 1 year after the injury for neuroimaging, neurochemical, neuropathological, and behavioral changes. The model is complementary to open skull models of controlled cortical impact using the same impactor device. Thus, labs can model both mild diffuse TBI and focal moderate-to-severe TBI with the same impactor.

The protocol describes mild traumatic brain injury in a mouse model. In particular, a step-by-step protocol to induce a mild midline closed head injury and the characterization of the animal model is fully explained.

小鼠轻度创伤性脑损伤的电磁控制闭头模型

Highly reproducible animal models of traumatic brain injury (TBI), with well-defined pathologies, are needed for testing therapeutic interventions and ...