1。成立控股动物和夹具设计的框架<ol><li>框架和钳举行动物是定制设计，以容纳无限的地平线（IH）脊髓损伤冲击。 </li><li>框架的基础是切成以下尺寸（30.2厘米×20.3厘米×1.3厘米），以适应来中转设备（ 图1A）标准表指南支架的铝制平台。 </li><li>四Flexaframe支持脚踏板（费希尔科学，多伦多，ON）连接平台和八个Flexaframe支持棒（尔科技，多伦多，30.5厘米）8 Flexaframe支持连接器（ 图1B）组装使用。 </li><li>另外两个Flexaframe支持连接器，连接到中间两棒，内部定制持有钳（ 图1B）。 </li><li>动物的脊髓是垂直旋转的角度，建立由keeping一年的水平杆的地方和不同高度的其他横向杆（ 图2）。 </li><li>钳是35.6毫米长，25.4毫米和7.6毫米颚硬性抢横突下方持有从C4至C6（ 图1C）。钳位设计上的更多细节已秋等 ，2009。 </li></ol> 2。手术<ol><li>雄性SD大鼠（查尔斯河实验室），体重300-350克异氟醚麻醉（归纳为4％和2％的维修），氧气（1升/分钟）。 </li><li>一旦麻醉平面下的动物，动物被放置在一个立体框架（Kopf，图洪加，CA）的。 </li><li>在手术过程0.4毫升的利多卡因（20毫克/毫升; Bimeda - MTC动物保健公司，剑桥大学，加拿大安大略省），以尽量减少出血肾上腺素肌肉注射周围手术部位在手背升颈部区域。 </li><li>一个4-5厘米的背正中切口用无菌手术刀（15号），从颅底和延伸尾端。 </li><li>使用无菌Adson钳直言不讳地剖析，以达到通过背部肌肉的脊椎，无菌ALM拉钩（精细的科学工具，北温哥华）被插入，以保持肌肉分开。 </li><li>用15号手术刀，C4〜C7椎板肌肉覆盖刮掉，在中线开始，席卷他们的横向。 </li><li>切口用无菌手术刀（15号），以适应钳下方的C4至C6横突附着在脊柱两侧横突的肌肉。 </li><li>用无菌罚款放倒弗里德曼皮尔逊咬骨钳（精细的科学工具，北温哥华），左侧C5椎板小心被删除，以可视化的硬脊膜和脊髓。 </li><li>与一个直径为1.5毫米的棒下武器下滑托动物，从而提高了脊柱略和促进钳插入。 </li><li>到C6 C4的上侧横向流程的无菌钳颚安装并拧紧螺丝。 </li><li>删除的ALM拉钩。 </li></ol> 3。脊髓损伤<ol><li>夹钳后，安装在动物，动物被移到中转冲击。 </li><li>钳插入帧的中间两棒角为22.5°的水平（ 图2）已抵押的金属支架。 </li><li>剪式千斤顶，提供稳定的高度调整，（厂商VWR，米西索加）提出，直到动物奠定了平坦的。 </li><li>确保钳钳上放置一个小缸水平和拧紧螺丝的水平。重要的是，所有螺丝都拧紧集是刚性没有任何运动。 </li><li>程序的其余部分进行下MICR的Oscope（MZ8徕卡）。 </li><li>降低和中转冲击垂直调节旋钮和两个水平调整旋钮，直到撞击尖端中心以上的5233棘突顶点徘徊，瞄准冲击小费（四舍五入的边缘，直径15毫米）。 </li><li>一旦撞击尖为中心，把Y轴调节旋钮和两个第五圈（1.4毫米）的尖端移动左侧和x轴水平调整旋钮横向移动撞击尖C5的中心。 </li><li>降低一角，直到它上面硬脑膜验证撞击尖瞄准灰质外侧半。 </li><li>转动两圈提高尖端毫米4硬脑膜以上的垂直调节旋钮。 </li><li>确保受影响的区域是用棉签或棍子干。 </li><li>设置150 kdyn程序所需的力，然后按一下“开始实验”引发的冲击。 </li><li>受伤后，伤口在Laye的封闭RS与5-0 vicryl缝线。丁丙诺啡（0.03毫克/千克SC，Temgesic; Kenilworth的先灵葆雅公司，新泽西州）和生理盐水（10毫升）皮下注射，每日两次手术后两天。动物密切监测，每天两次为2周，伤后6周每周。 </li></ol> 4。代表结果受伤在150 kdyn的力设置二十九个雄性SD大鼠（查尔斯河实验室），体重300-350克。旨在撞击尖到中线1.4 mm处，在22.5°垂直角度。平均实际力量是155.55±0.73 kdyn。平均排量为1512.72±27.86μm和速度是120.24±0.52毫米/秒（ 图3）。 行为成果措施水平的阶梯测试，饲养试验缸，梳洗测试，评估使用功能恢复，修改的蒙托亚楼梯测试1。动物受伤前的培训，并在伤后2，4和6周的评估。有显着前肢在整个实验期内持续的障碍。 受伤前的水平梯试验。，动物只有4.75±0.73％同侧前肢错误而穿越整个间隔不规则的横梯。受伤之后，动物的证明标记在前肢错误的百分比增加。同侧前肢％误差分别为26.97±2.92％，26.23±2.84％和22.06±2.05％2，伤后4周和6周，分别为（ 图4A）。重要的是，本次测试的前肢减值持续6周。 缸饲养试验。同侧前肢的百分比（左+都）在勘探过程中使用SCI后显着下降。受伤前，动物用同侧前肢75.12±2.25％。受伤后，动物用同侧前肢8.59±1.80％2周，14.25±2.65％，4周和11.76±2.66％，在6个星期（ 图4B）。 修改蒙托亚楼梯测试。同侧前肢检索的颗粒数量急剧下降后的损伤。受伤之前，收集的动物食物奖励84.85±2.88％。然而，在伤后2，4和6周，检索的动物只有30.91±4.03％，28.94±4.38％和25.86±3.09％的颗粒（ 图4C）。 美容测试。在受伤后的仪容分数有大幅度降低。脊髓损伤后，同侧疏导分数分别为2周：2.00±0.17，4周：1.83±0.17和6周：1.79±0.11（Figu重新4D）。 病理结果白质和灰质备用。例如在了150 kdyn的力量，角度为22.5°和1.4毫米的横向目标的脊髓损伤是在图5。损伤造成实质性损害同侧灰质和白质。皮质和红核脊髓束都受伤，23出29只动物有同侧内的实质损害。纵向的白色和灰色的事情损害程度是2400 rostrally和2400尾端（ 图6）。当加入的部分提供了总值估计“累积蔓延”（2000微米的喙和尾震中）的白色和灰色的物质备用，同侧白色幸免问题只有51.8％和39.7％灰质剩余相比，对侧（ 图6）。 &lt;IMG ALT =“图1”的src =“/ files/ftp_upload/3313/3313fig1.jpg”/&gt; 图1。无穷水平脊髓损伤的冲击。答：无限的地平线冲击和整体设置。 B.帧设置。 C.特写图像颈椎横突钳。 D.规格（单位：英寸）的钳。建议公差&lt;0.002（秋等人 ，2009年）。 <a href="http://www.jove.com/files/ftp_upload/3313/3313fig1large.jpg" target="_blank">点击这里查看大图</a> 。 <img alt="图2" src="/files/ftp_upload/3313/3313fig2.jpg" /> 图2。插图和相应的帧设置要达到1.4毫米的横向目的脊髓旋转0°（中性）或B。22.5°。 <img alt="图3" src="/files/ftp_upload/3313/3313fig3.jpg" /> 图3。代表力量和位移图的无限地平线冲击。我箭头ndicates撞击尖已达20 kdyn启动时记录位移点的时间。力随时间变化曲线的峰值读取实际的力量和相应的位移计算。下面的图表描绘一个典型的150 kdyn挫伤，A.位移随时间变化图，B.力与时间的关系图。这些图表表明，取得的实际力量是152 kdyn，和冲击位移到线测量是1287微米。 <a href="/files/ftp_upload/3313/3313fig3large.jpg" target="_blank">点击这里查看大图</a> 。 <img alt="图4" src="/files/ftp_upload/3313/3313fig4.jpg" /> 图4。力150 kdyn，冲击角为22.5°和1.4毫米的目的的行为评估留下的中线。水平梯试验。 B.缸饲养试验。 C.修改的蒙托亚楼梯测试。四美容测试。同侧前肢导致重大和sustai的NED障碍较对侧前肢。 <img alt="图5" src="/files/ftp_upload/3313/3313fig5.jpg" /> 图5。受伤的脊髓延髓1600微米至尾鳍1600微米的代表图像。 <img alt="图6" src="/files/ftp_upload/3313/3313fig6.jpg" /> 图6。组织学评估。 ％的白人和灰质幸免。重要损害震中微米，大约是2000年在很大程度上幸免。 B.累积白色和灰质损害震中在2000微米幸免。同侧明显少幸免白色和灰色的事情相比，对侧。 <a href="/files/ftp_upload/3313/3313fig6large.jpg" target="_blank">点击这里查看大图</a> 。

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没有利益冲突的声明。

在本文中，我们描述了颈椎的单方面挫伤模型，使用在150 kdyn，关闭垂直角为22.5°，和一个1.4毫米的中线外侧目的的力量无限的地平线（IH）的冲击。通过这些设置，我们能够产生持续的行为，在所载主要同侧的实质破坏，同侧前肢的赤字，它出现相当大的损害发生地区的红核脊髓，网状，前庭和皮质脊髓束将有望运行。这种模式的发展发生了一系列的三个实验确定最佳的伤害力，影响中线的位置...

<table border="1"><tbody><tr><td> 设备名称 </td><td> 公司 </td><td> 目录编号 </td><td> 评论 </td></tr><tr><td>无限地平线冲击</td><td>精密系统和仪器仪表</td><td>中转-0400 </td><td></td></tr><tr><td>铝金属片</td><td> Metalsupermarlets.com </td><td> APT6061/500 </td><td></td></tr><tr><td> flexaframe支持脚板</td><td>渔民科学</td><td> 1466625Q </td><td></td></tr><tr><td> flexaframe支持棒</td><td>渔民科学</td><td> 1466610GQ </td><td></td></tr><tr><td> flexaframe支持连接器</td><td>渔民科学</td><td> 1466620Q </td><td></td></tr><tr><td>钳1 </td><td>定制</td><td></td><td>秋等人 。2009年</td></tr><tr><td>金属支架</td><td>定制</td><td></td><td>见上文</td></tr><tr><td>撞击尖</td><td>定制</td><td></td><td>直径：1.15毫米</td></tr><tr><td>立体框架</td><td>大卫Kopf仪器</td><td>型号900 </td><td></td></tr><tr><td>气缸水平</td><td>益佳工具</td><td> YJ-SL0620 </td><td></td></tr><tr><td>显微镜</td><td>徕卡</td><td></td><td>型号＃：MZ8 </td></tr><tr><td>实验室剪式插孔</td><td>厂商VWR </td><td> 12620-902 </td><td></td></tr></tbody></table>

a contusive model of unilateral cervical spinal cord injury using the infinite horizon impactor

虽然大多数人的脊髓损伤，脊髓型颈椎病的发生，实验室研究的绝大多数员工在胸段脊髓受伤的脊髓损伤（SCI）的动物模型。此外，因为大多数人的脊髓损伤发生钝，非穿透性创伤（如机动车事故，运动伤害），脊髓被猛烈袭击流离失所的骨或软组织的结果，多数脊髓损伤的研究人员认为临床最相关的损伤模型是那些在脊髓迅速被撞伤。因此，在他们的方式对人类翻译的新疗法的临床前评价的重要的一步是评估其疗效挫伤脊髓损伤模型内脊髓型颈椎病。在这里，我们描述的技术方面和解剖和行为产生的单方面颈椎脊髓挫伤模型的成果，它采用了无限的地平线脊髓损伤撞击。 在C5 SD大鼠行单侧椎板左片面。以优化生物力学，功能和组织损伤模型结果的重复性，我们挫伤脊髓使用150 kdyn，影响力，22.5°（22.5°旋转的动物）的影响轨迹，影响位置关闭1.4毫米的中线。功能恢复使用缸饲养试验，阶梯测试水平，疏导长达6周的试验和改良蒙托亚的楼梯测试评估后，其中的脊髓进行了评估组织为白色和灰色的事情备用。 这里的损伤模型赋予一致的和可再生的生物力学部队到脊髓，任何实验性脊髓损伤模型的一个重要特征。在离散组织损伤脊髓侧半这结果主要包含到T他同侧伤害。伤害动物的耐受性良好，但在前肢的功能是在损伤后的周显著和持续的赤字。颈椎单方面损伤模型，这里可能是那些希望评估具有潜力的治疗之前，人类翻译研究的资源。

Watch this Scientific Journal Video about A Contusive Model of Unilateral Cervical Spinal Cord Injury Using the Infinite Horizon Impactor at JoVE.com

A Contusive Model of Unilateral Cervical Spinal Cord Injury Using the Infinite Horizon Impactor

描述一个可靠和可重复的方式来生产使用无限的地平线撞击宫颈单方面脊髓损伤。该方法采用自定义设计的框架的优势和取缔，以稳定脊柱。标准化的程序和损伤生物力学参数足够和持续的伤害结果。

单侧颈脊髓损伤的挫伤模型，利用无限的地平线冲击

While the majority of human spinal cord injuries occur in the cervical spinal cord, the vast majority of laboratory research employs animal models of ...

a-contusive-model-unilateral-cervical-spinal-cord-injury-using

Research

JoVE Journal

Medicine

19.3K 次观看.  University of British Columbia. 描述一个可靠和可重复的方式来生产使用无限的地平线撞击宫颈单方面脊髓损伤。该方法采用自定义设计的框架的优势和取缔，以稳定脊柱。标准化的程序和损伤生物力学参数足够和持续的伤害结果。

视频: A Contusive Model of Unilateral Cervical Spinal Cord Injury Using the Infinite Horizon Impactor

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

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

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

在大鼠脊髓损伤后的急性和慢性触觉测试

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

科研

医学

Controlled Cervical Laceration Injury in Mice

Use of genetically modified mice enhances our understanding of molecular mechanisms underlying several neurological disorders such as a spinal cord injury (SCI). Freehand manual control used to produce a laceration model of SCI creates inconsistent injuries often associated with a crush or contusion component and, therefore, a novel technique was developed. Our model of cervical laceration SCI has resolved inherent difficulties with the freehand method by incorporating 1) cervical vertebral stabilization by vertebral facet fixation, 2) enhanced spinal cord exposure, and 3) creation of a reproducible laceration of the spinal cord using an oscillating blade with an accuracy of &plusmn;0.01 mm in depth without associated contusion. Compared to the standard methods of creating a SCI laceration such as freehand use of a scalpel or scissors, our method has produced a consistent lesion. This method is useful for studies on axonal regeneration of corticospinal, rubrospinal, and dorsal ascending tracts.

A novel technique to create a reproducible in vivo model of cervical spinal cord laceration injury in the mouse is described. This technique is based on spine stabilization by fixation of the cervical facets and laceration of the spinal cord using an oscillating blade with an accuracy of &plusmn;0.01 mm.

控制宫颈裂伤损伤小鼠

Use of genetically modified mice enhances our  understanding of molecular mechanisms underlying several neurological disorders  such as a spinal cord ...

A Contusion Model of Severe Spinal Cord Injury in Rats

The translational potential of novel treatments should be investigated in severe spinal cord injury (SCI) contusion models. A detailed methodology is described to obtain a consistent model of severe SCI. Use of a stereotactic frame and computer controlled impactor allows for creation of reproducible injury. Hypothermia and urinary tract infection pose significant challenges in the post-operative period. Careful monitoring of animals with daily weight recording and bladder expression allows for early detection of post-operative complications. The functional results of this contusion model are equivalent to transection models. The contusion model can be utilized to evaluate the efficacy of both neuroprotective and neuroregenerative approaches.

A contusion model of severe spinal cord injury is described. Detailed pre-operative, operative and post-operative steps are described to obtain a consistent model.

挫伤模型脊髓严重损伤的保护作用

The translational potential of novel treatments should be investigated in severe spinal cord injury (SCI) contusion models. A detailed methodology is ...

A Novel Vertebral Stabilization Method for Producing  Contusive Spinal Cord Injury

Clinically-relevant animal cervical spinal cord injury (SCI) models are essential for developing and testing potential therapies; however, producing reliable cervical SCI is difficult due to lack of satisfactory methods of vertebral stabilization. The conventional method to stabilize the spine is to suspend the rostral and caudal cervical spine via clamps attached to cervical spinous processes. &#160;However, this method of stabilization fails to prevent tissue yielding during the contusion as the cervical spinal processes are too short to be effectively secured by the clamps (Figure 1). &#160;Here we introduce a new method to completely stabilize the cervical vertebra at the same level of the impact injury. &#160;This method effectively minimizes movement of the spinal column at the site of impact, which greatly improves the production of consistent SCIs. &#160;We provide visual description of the equipment (Figure 2-4), methods, and a step-by-step protocol for the stabilization of the cervical 5 vertebra (C5) of adult rats, to perform laminectomy (Figure 5) and produce a contusive SCI thereafter. &#160;Although we only demonstrate a cervical hemi-contusion using the NYU/MASCIS impactor device, this vertebral stabilization technique can be applied to other regions of the spinal cord, or be adapted to other SCI devices. &#160;Improving spinal cord exposure and fixation through vertebral stabilization may be valuable for producing consistent and reliable injuries to the spinal cord. &#160;This vertebral stabilization method can also be used for stereotactic injections of cells and tracers, and for imaging using two-photon microscopy in various neurobiological studies.

Vertebral stabilization is necessary for minimizing variability, and for producing consistent experimental spinal cord injuries.&#160; Using a customized stabilizing apparatus in conjunction with the NYU/MASCIS impactor device, we have demonstrated here the proper equipment and procedure for generating reproducible hemi-contusive cervical (C5) spinal cord injuries in adult rats.

一种新的椎稳定制备方法挫伤脊髓损伤

Clinically-relevant animal cervical spinal cord injury (SCI) models are essential for developing and testing potential therapies; however, producing ...

A Murine Model of Cervical Spinal Cord Injury to Study Post-lesional Respiratory Neuroplasticity

A cervical spinal cord injury induces permanent paralysis, and often leads to respiratory distress. To date, no efficient therapeutics have been developed to improve/ameliorate the respiratory failure following high cervical spinal cord injury (SCI). Here we propose a murine pre-clinical model of high SCI at the cervical 2 (C2) metameric level to study diverse post-lesional respiratory neuroplasticity. The technique consists of a surgical partial injury at the C2 level, which will induce a hemiparalysis of the diaphragm due to a deafferentation of the phrenic motoneurons from the respiratory centers located in the brainstem. The contralateral side of the injury remains intact and allows the animal recovery. Unlike other SCIs which affect the locomotor function (at the thoracic and lumbar level), the respiratory function does not require animal motivation and the quantification of the deficit/recovery can be easily performed (diaphragm and phrenic nerve recordings, whole body ventilation). This pre-clinical C2 SCI model is a powerful, useful, and reliable pre-clinical model to study various respiratory and non-respiratory neuroplasticity events at different levels (molecular to physiology) and to test diverse putative therapeutic strategies which might improve the respiration in SCI patients.

Respiratory failure is the leading cause of death following a cervical spinal cord injury. Having a reproducible, quantifiable, and reliable pre-clinical animal model of respiratory failure induced by a partial cervical injury will help to understand the subsequent respiratory and non-respiratory neuroplasticity and allow testing putative repair strategies.

颈脊髓损伤的小鼠模型研究后皮损呼吸神经可塑性

A cervical spinal cord injury induces permanent paralysis, and often leads to respiratory distress. To date, no efficient therapeutics have been developed ...

Controlled Cortical Impact Model for Traumatic Brain Injury

Every year over a million Americans suffer a traumatic brain injury (TBI). Combined with the incidence of TBIs worldwide, the physical, emotional, social, and economical effects are staggering. Therefore, further research into the effects of TBI and effective treatments is necessary. The controlled cortical impact (CCI) model induces traumatic brain injuries ranging from mild to severe. This method uses a rigid impactor to deliver mechanical energy to an intact dura exposed following a craniectomy. Impact is made under precise parameters at a set velocity to achieve a pre-determined deformation depth. Although other TBI models, such as weight drop and fluid percussion, exist, CCI is more accurate, easier to control, and most importantly, produces traumatic brain injuries similar to those seen in humans. However, no TBI model is currently able to reproduce pathological changes identical to those seen in human patients. The CCI model allows investigation into the short-term and long-term effects of TBI, such as neuronal death, memory deficits, and cerebral edema, as well as potential therapeutic treatments for TBI.

Traumatic brain injuries (TBIs) remain a serious health problem. Using the controlled cortical impact surgery model, research on the effects of TBI and possible treatment methods may be performed.

控制皮层影响模型创伤性脑损伤

Every year over a million Americans suffer a traumatic brain injury (TBI).  Combined with the incidence of TBIs worldwide, the physical, emotional, ...

A Radio-telemetric System to Monitor Cardiovascular Function in Rats with Spinal Cord Transection and Embryonic Neural Stem Cell Grafts

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter connected to a radio transmitter into the femoral artery of rats that underwent a T4 spinal cord transection with or without grafting of embryonic brainstem-derived neural stem cells expressing green fluorescent protein. Compared to other methods such as cannula insertion or tail-cuff, telemetry is advantageous to continuously monitor blood pressure and heart rate in freely moving animals. It is also capable of long term multiple data acquisitions. In spinal cord injured rats, basal cardiovascular data under unrestrained condition and autonomic dysreflexia in response to colorectal distension were successfully recorded. In addition, cardiovascular parameters before and after SCI can be compared in the same rat if a transmitter is implanted before a spinal cord transection. One limitation of the described telemetry procedure is that implantation in the femoral artery may influence the blood supply to the ipsilateral hindlimb.

We present a protocol for using a radio-telemetric system to record cardiovascular parameters in T4 spinal cord transected rats eight weeks after embryonic brainstem neural stem cell grafting into the lesion site. Telemetry is an advanced technique to accurately evaluate cardiovascular function in conscious freely moving spinal cord injured rats.

无线电遥测系统，以监测大鼠脊髓横断和胚胎神经干细胞移植在心血管功能

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter ...

Synergetic Use of Neural Precursor Cells and Self-assembling Peptides in Experimental Cervical Spinal Cord Injury

Spinal cord injuries (SCI) cause serious neurological impairment and psychological, economic, and social consequences for patients and their families. Clinically, more than 50% of SCI affect the cervical spine1. As a consequence of the primary injury, a cascade of secondary mechanisms including inflammation, apoptosis, and demyelination occur finally leading to tissue scarring and development of intramedullary cavities2,3. Both represent physical and chemical barriers to cell transplantation, integration, and regeneration. Therefore, shaping the inhibitory environment and bridging cavities to create a supportive milieu for cell transplantation and regeneration is a promising therapeutic target4. Here, a contusion/compression model of cervical SCI using an aneurysm clip is described. This model is more clinically relevant than other experimental models, since complete transection or ruptures of the cord are rare. Also in comparison to the weight drop model, which in particular damage the dorsum columns, circumferential compression of the spinal cord appears advantageous. Clip closing force and duration can be adjusted to achieve different injury severity. A ring spring facilitates precise calibration and constancy of clip force. Under physiological conditions, synthetic self-assembling peptides (SAP) self-assemble into nanofibers and thus, are appealing for application in SCI5. They can be injected directly into the lesion minimizing damage to the cord. SAPs are biocompatible structures erecting scaffolds to bridge intramedullary cavities and thus, equip the damaged cord for regenerative treatments. K2(QL)6K2 (QL6) is a novel SAP introduced by Dong et al.6 In comparison to other peptides, QL6 self-assembles into &#946;-sheets at neutral pH6.14 days after SCI, after the acute stage, SAPs are injected into the center of the lesion and neural precursor cells (NPC) are injected into adjacent dorsal columns. In order to support cell survival, transplantation is combined with continuous subdural administration of growth factors by osmotic micro pumps for 7 days.

Treating cervical spinal cord injury with both self-assembling peptides (SAP) and neural precursor cells (NPC), together with growth factors, is a promising approach to promote regeneration and recovery. A contusion/compression aneurysm clip rat model of cervical SCI and combined treatment involving SAP injection and NPC transplantation is established.

在实验颈脊髓损伤协同使用神经前体细胞，并自组装肽的

Spinal cord injuries (SCI) cause serious neurological impairment and psychological, economic, and social consequences for patients and their families. ...

Neural Stem Cell Transplantation in Experimental Contusive Model of Spinal Cord Injury

Spinal cord injury is a devastating clinical condition, characterized by a complex of neurological dysfunctions. Animal models of spinal cord injury can be used both to investigate the biological responses to injury and to test potential therapies. Contusion or compression injury delivered to the surgically exposed spinal cord are the most widely used models of the pathology. In this report the experimental contusion is performed by using the Infinite Horizon (IH) Impactor device, which allows the creation of a reproducible injury animal model through definition of specific injury parameters. Stem cell transplantation is commonly considered a potentially useful strategy for curing this debilitating condition. Numerous studies have evaluated the effects of transplanting a variety of stem cells. Here we demonstrate an adapted method for spinal cord injury followed by tail vein injection of cells in CD1 mice. In short, we provide procedures for: i) cell labeling with a vital tracer, ii) pre-operative care of mice, iii) execution of a contusive spinal cord injury, and iv) intravenous administration of post mortem neural precursors. This contusion model can be utilized to evaluate the efficacy and safety of stem cell transplantation in a regenerative medicine approach.

Spinal cord injury is a traumatic condition that causes severe morbidity and high mortality. In this work we describe in detail a contusion model of spinal cord injury in mice followed by a transplantation of neural stem cells.

在脊髓损伤的实验挫伤型号神经干细胞移植

Spinal cord injury is a devastating clinical condition, characterized by a complex of neurological dysfunctions. Animal models of spinal cord injury can ...

Calibrated Forceps Model of Spinal Cord Compression Injury

Compression injuries of the murine spinal cord are valuable animal models for the study of spinal cord injury (SCI) and spinal regenerative therapy. The calibrated forceps model of compression injury is a convenient, low cost, and very reproducible animal model for SCI. We used a pair of modified forceps in accordance with the method published by Plemel et al. (2008) to laterally compress the spinal cord to a distance of 0.35 mm. In this video, we will demonstrate a dorsal laminectomy to expose the spinal cord, followed by compression of the spinal cord with the modified forceps. In the video, we will also address issues related to the care of paraplegic laboratory animals. This injury model produces mice that exhibit impairment in sensation, as well as impaired hindlimb locomotor function. Furthermore, this method of injury produces consistent aberrations in the pathology of the SCI, as determined by immunohistochemical methods. After watching this video, viewers should be able to determine the necessary supplies and methods for producing SCI of various severities in the mouse for studies on SCI and/or treatments designed to mitigate impairment after injury.

Spinal cord injury models should be highly reproducible. We demonstrate that the calibrated forceps compression model of spinal cord injury is an easy to use surgical method for generating reproducible injuries to the murine spinal cord.

脊髓压迫损伤的校准钳型

Compression injuries of the murine spinal cord are valuable animal models for the study of spinal cord injury (SCI) and spinal regenerative therapy. The ...