NS43798（DMB），国立卫生研究院NIH的F31的NS058138（MRD）的; P30-NS045758（CBSCR）;＃2451（DMB）和2707（MRD）的美国瘫痪退伍军人。

1。向上/向下跖用von Frey测试测试的目的是通过测量确定需要多大的力引起爪子撤回刺激触觉的敏感度。市售标准von Frey 4.56和6.10的范围之间的发单丝用于刺激爪子。可视化的刺激或本体感觉输入其他类似可以混淆触觉阈值的措施，所以基于视觉或本体输入的反应是无效的。为了防止接触皮肤的单丝的可视化，我们只测试而老鼠吃谷物。这种认知分心，也确保所有大鼠在相似的舒适基线水平测试。为了避免由于本体，而不是触觉输入的响应，我们不包括单丝升降机或移动爪子的试验。 A.向上向下的方法驯化程序<ol><li>当前水果cerea在家里笼l使大鼠的认识和寻找食物奖励。大鼠不需要是在被剥夺在gentling或测试过程中任何一点的食物。 </li><li>老鼠被驯化的测试环境和程序，一旦他们在家里笼吃水果谷物。驯化发生了至少4个会议，但更可能需要10分钟。使老鼠不成为酒足饭饱在会议结束前十分钟会议。 </li><li>大鼠在试验室将与三件水果谷物。提供额外的水果谷物作为他们吃的时间到两个。第三次会议上的老鼠吃时，生产线地板下的手部动作，使老鼠变得习惯于它的爪子下的运动。在第四次会议上，适用于5.18单丝足底表面的爪子，一次约一分钟共十场专题介绍。一个天真的老鼠不应该响应本次阈值刺激。 </li><li>高y的件消耗的谷物，排尿和排便，冻结，仪容行为的频率。冻结行为发生在两个方面：一）对大鼠低到靠近后墙的地面通常蹲在或面临从考官依然一动不动;二）对大鼠弓着背在笼中，通常是非者，它的牙齿。冻结行为可能会持续很长一段时间。 </li><li>是的一个gentled老鼠准备测试将连续吃了近10分钟。这将很容易地在笼子里，后消费的最后寻求水果谷物很快。重要的是，老鼠会不会停止进食或线下的地面或单丝应用的爪子的手部动作而分心。 </li></ol> B.向上向下的方法测试程序<ol><li>大鼠产生窘迫发声，是我们人类的听觉范围以上。大鼠等待测试应保持在一个单独的房间，使他们无法听到这些VOCalizations。 </li><li>大鼠脊髓损伤是适当上下冯弗雷头发测试必须展示出四肢负重。是无法支持的大鼠的四肢不能可靠的测试，因为单丝的应用，移动前的头发弯曲的爪子。 </li><li>在大鼠试验室将有2或3件水果谷物。大鼠必须吃期间每个VFH应用。 </li><li>滚动骰子，以确定这红莲开始测试第一。偶数代表权的爪子，奇数代表左侧。 </li><li>开始测试5.18单丝会议。在正常和SCI大鼠戒断反应，可能会出现从4.56至6.10和5.18单丝在属于该范围的中间。 </li><li>老鼠冻结，蹲或不吃饭，不适用单丝。如果测试仪等，这些条件有时会解决和测试就可以恢复。如果老鼠显示这些行为和应用程序的总时间aratus是20分钟，停止测试和复试从一开始的第二天。不要删除大鼠，而它显示这些行为，因为这可能会增加其发生。等待，直到老鼠打破了这些模式前处理，以避免加强这些行为。 </li><li>轻触单丝对L5之间，直到它弯曲（ 见图1A）脚垫后肢足底皮。这光滑的稳定应用应约一秒钟，然后从皮肤移除。避免接触的垫脚的任何部分，作为皮肤的敏感性是在这些领域的低得多。这种单一的触摸构成一项试验。 </li><li>发生时，老鼠很快举起爪子从单丝远离正面回应。单丝被删除时必须开始撤离，以确认单丝的应用响应。 </li><li>其他证据意识，莫看动物nofilament触摸，如发声，眼睛向下，向后，或在测试的爪子，舔爪子，的持续爪子撤出或抽动耳朵。注意在数据表上它们。当这些行为发生爪子撤出它充当刺激脊髓感知的证据。 </li><li>如果有一个积极的回应，适用于下一个最低的单丝。如果没有任何反应（负），移动到下一个更高的单丝。让每个单丝申请复检（以防止适应）回来之前基线射击的感受器之间的30秒。 </li><li>继续申请更高或更低的单丝后肢的基础上积极或消极的反应，直到你有10个试验。然后重复其他后肢。 （例如表）。 </li><li>的的VFH，可以在不引入本体输入和解除爪子测试最高为6.10。 6.45VFH和较大的不应该使用，因为爪子前monof的升降机ilament弯曲。如果有在6.10没有响应，那么接下来的审判将再次申请的6.10。 </li><li>一个响应，应作废和审判必须重新测试，如果下列之一发生在刺激应用程序或缩爪： <ol class="lalpha"><li>大鼠连续吃。 </li><li>从VFH刺激老鼠移开之前的单丝弯曲，使其无法知道的力引起戒断反应。 </li><li>爪子被解除VFH提供本体中除了触觉刺激（无论之前或之后的VFH是弯曲的）。 </li></ol></li><li>测试会话通常为两后肢在不到15分钟就可以完成。 </li></ol> C.数据处理方法上下<ol><li>测试成功，将有10个连续试验，每个爪子。 </li><li>触觉阈值的值是最低的单丝产生爪子＆G撤出E，50％的介绍和3个或更多的介绍单丝（见示例表，阈值盘旋）。 </li><li>一个只有2总试验单丝未选中作为阈值，即使当一个审判是积极的，一个是否定的。多个演示文稿的刺激的反应模式，更好的指标，以武力。 </li><li>如果没有单丝产生的积极响应，至少50％的测试，大鼠给予6.45分。这意味着，老鼠没有检测到6.10测试的最高单丝超出随机机会。值6.45，因为它代表了未来的价值高于单丝测试的范围。 </li><li>转换成克力的左，右爪子的阈值。冯弗雷头发的供应商将提供克的力值。 。为来自双边受伤的数据，两个爪子的门槛克力可以平均产生一个单一的得分。 </li></ol> 2。背冯弗雷测试本试验的目的是确定在这样恶劣的马达控制，他们不能使用典型足底VFH方法测试大鼠的触觉灵敏度。它量化多少触摸力产生厌恶反应。为了避免本体刺激的反应，我们不包括的爪子在申请提出的VFH试验。此外，我们不包括试验中，VFH滑倒或整个足背表面刷。 A.背用von Frey测试驯化程序<ol><li>温柔四，每次10分钟的会议之前，基准测试和脊髓损伤大鼠。 </li><li>松散的小毛巾敷大鼠，使后躯暴露所示（ 图1B）。位置与大鼠后爪轻轻地搁在表面上超过表。使用相同的舒适但不紧包装和持有每只大鼠。你的前臂支撑在桌子的边缘，可能会减少之间大鼠变异。 </li><li>是的一个gentled老鼠准备好测试不会抗拒在毛巾举行连续数分钟，但你可能要重新包装大鼠1或2次测试过程中的两个后爪。 </li></ol> B.背用von Frey测试的测试程序<ol><li>滚动骰子来决定首先开始测试后肢。偶数代表权的爪子，奇数代表左侧。 </li><li>松散的包裹在毛巾离开后躯暴露大鼠。 </li><li>触觉刺激应用于只老鼠后是平静的，至少10秒钟的安静。 </li><li> 4.56 VFH开始，适用于单丝垂直于背表面的第一和第二跖骨之间约1厘米的近端关节（ 图1C）。应用单丝平稳，STEADY方式，超过一秒钟的间隔，直到它弯曲，然后将其删除。这种单一的触摸构成一项试验。 </li><li>一个积极的反应发生时，老鼠迅速移动从刺激的爪子。经常运动的方向是后或外部，前后肢弯曲。单丝被删除时必须开始撤离，以确认单丝的应用响应。 </li><li>申请4.56单丝为了防止感官“发条”，并允许感受器回来基线复检前发射（以防止适应）与应用程序之间的至少30秒的两倍多。 </li><li>刺激试验应重新申请，如果的VFH单，轻轻擦过皮肤，使更多的刷牙或尖的接触，而不是扫描的力量投送。 </li><li>如果有超过2 4.56单丝（即0或1）更少的积极响应，下一个较大的VFH应用3次以同样的方式。 </li><li>这种方式在逐渐变大，4.56至5.88 VFHs直到出现两个或两个以上的积极响应，直到达到最大VFH。 </li><li>缩爪阈值是最低的VFH这引起了3个试验至少2个正面的回应。 </li><li>重复其他爪子。 </li><li>测试会话通常可以在15分钟后爪为完成。 </li></ol> 3。代表结果一个成功的测试将导致立即，快步撤离到一个垂直应用VFH后肢从联合（ 图1C）中期的足底地区（ 图1A）或背水面之间的第一和第二跖骨1厘米。这些反应是相吻合，获得每个后肢触觉门槛。触觉阈值从急性脊髓背VFH测试显示了良好的保真度与足底的VFH阈值派生D慢性倍（ 图2）。发生足底或背测试所得的触觉阈值下降梯度SCI（ 图3 3,5）。这种过敏反应表现为早7天，脊髓损伤后和实验期3-4,6维持。而脊髓损伤的严重程度不影响触觉阈值的爪子，在阈值下降发生更严重的SCI（ 图3）。重要的是，以下的水平痛觉异常的发展，是一个全或无反应发生时，有超过60％的脑白质病变​​震中损失。 （ 图3）。 触觉阈值衰减和生产人造低VFH部队。至少有两个条件，可以产生阈值衰减 - 迅速应用VFH的皮肤在戳或猛刺方式或不刺激的应用程序之间的等待足够长的时间。有信心是真正的触觉阈值时，必须采取适用于每个的VFH使用类似的低速方式和刺激间隔必须至少30秒。我们还表明，饮食行为，降低门槛衰变5。 <img alt="图1" src="/files/ftp_upload/3247/3247fig1.jpg" /> 图1描绘的VFH刺激足底和背冯弗雷头发（VFH）测试位置示意图和照片。一）对于足底VFH测试，冯弗雷头发应适用于垂直中期足底后肢约1厘米后，在一个缓慢的中间指骨（红色框表示在图的后肢足底表面）速度一致，直到它弯曲。 B和C）背VFH技术，是松散的大鼠在手术巾包裹，如照片中所示。 VFH被应用到背表面的爪子之间的第一和第二跖骨approximatelY 1厘米，近端关节。 <img alt="图2" src="/files/ftp_upload/3247/3247fig2.jpg" /> 图2。背冯弗雷头发的感觉阈值与标准足底VFH。 （N-44，Pearson相关系数= 0.503，P &lt;0.01，R2 = 0.67）。虚线表明痛觉超敏感的临界阈值，使用背的的VFH或足底VFH技术，并表明在脊髓损伤后7天使用背VFH测试，痛觉超敏阈值预测慢性以下级痛觉异常足底VFH方法确定的。 <img alt="图3" src="/files/ftp_upload/3247/3247fig3.jpg" /> 图3。早期背冯弗雷头发的感觉阈值预测痛觉超敏和非痛觉超敏的触觉灵敏度，跨在稍后时间点的伤害严重性。类似的感觉阈值之间发生后脊髓背VFH和28天后脊髓损伤足底VFH措施7天。发生了惊人的相似<html>广泛的脊髓损伤，显着的异常性疼痛，指出在中度至重度脊髓损伤（P &lt;.05 1.1毫米与其他各组位移）。 <img alt="图4" src="/files/ftp_upload/3247/3247fig4.jpg" /> 图4。接受椎板切除术（无脊髓损伤）的大鼠和SCI组脊髓损伤后后肢痛觉异常显示在6个星期的百分比。痛觉异常仅见于大鼠中度或重度SCI（俄勒冈州立大学ESCID设备0.9，1.1，1.25，1.3毫米线位移），而轻度脊髓损伤的大鼠（0.3，0.5，0.7毫米的脊髓位移）展出触觉刺激的正常反应。代表冠状脊髓部分髓鞘染色病变椎板震中（无恙控制），轻度（0.5毫米的位移），中度（1.1毫米的位移）和严重（1.3毫米的位移）脊髓挫伤包括显示轴索程度不遗余力，过敏与此相关。 （比例尺= 0.5毫米）。 K“&gt; <img alt="图5" src="/files/ftp_upload/3247/3247fig5.jpg" /> 图5。冯弗雷上下发测试的样本数据表。头发的价值和结果（正或负），记录每个审判。指出测试脊髓意识的迹象。在测试结束时，在每发价值的反应相吻合。例如数据为选定的阈值盘旋。

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作者没有透露。

在这里代表的的VFH测试方法提出两个敏感和有效的使用在大鼠脊髓损伤模型的测试范例。重要的是，背VFH测试创建评估触觉敏锐中期胸椎脊髓损伤大鼠时无法站立，他们的后躯，后肢爪子恢复。此测试范例也可以用来当老鼠恢复的能力，以支持他们的体重和颈椎脊髓损伤后后肢。 两种范式表明，这里利用校准的VFH以确定每个后肢触觉阈值。其他方法确定撤出无论是正常无害?...

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acute and chronic tactile sensory testing after spinal cord injury in rats

脊髓损伤（SCI）损害造成1-8异常性疼痛的感觉系统。以确定细胞和分子的原因，痛觉异常敏感和有效的在大鼠脊髓损伤模型的感官检验是​​必要的。然而，直到最近，没有一个单一的测试方法已验证SCI，使标准化的方法尚未在实验室实施。此外，现有的测试方法不能实施，急性或严重的运动障碍存在时，防止脊髓损伤引起的痛觉异常3发展的研究。在这里，我们提出了两个有效的感官检验方法冯弗雷头发（VFH）单丝，量化脊髓损伤后4-5触觉阈值的变化。一个测试，是行之有效的向上向下的测试表明，灵敏度高，特异性在不同脊髓损伤的严重程度进行测试时，长期5。其他的测试是一个新开发的背的VFH测试，可应用于脊髓损伤后急性时llodynia的发展，电机恢复4-5前。每个的VFH单丝适用于校准的力时，触及到的皮肤，直到它弯曲的爪。在上下的方法，更高或更低的势力交替VFHs使用足底L5皮划定屈撤回阈值。先后更高的势力施加撤军，直到出现较低的力量VFHs直到撤出不再使用。触觉阈值反映需要引起撤出50％的刺激力。对于新的测试，每个的VFH是爪子L5背皮，而老鼠是由考官支持。的的VFH刺激发生升序秩序的力量，直到至少2 3应用在一个给定的力量，产生缩爪。触觉阈值是最低的力量引起撤出66％的时间。驯化，测试和评分过程进行了描述。定义异常试验，认为需要复验和典型试验。动物USE W由美国俄亥俄州立大学动物照顾与使用委员会批准。

Watch this Scientific Journal Video about Acute and Chronic Tactile Sensory Testing after Spinal Cord Injury in Rats at JoVE.com

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

我们描述了两个在大鼠脊髓损伤的急性或慢性期的触觉感官检验方法。这些验证程序，可以检测痛觉异常，像感觉的开发和维护。

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 ...

acute-chronic-tactile-sensory-testing-after-spinal-cord-injury

Research

JoVE Journal

Medicine

23.5K 次观看.  School of Allied Medical Professions, The Ohio State University. 我们描述了两个在大鼠脊髓损伤的急性或慢性期的触觉感官检验方法。这些验证程序，可以检测痛觉异常，像感觉的开发和维护。

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

Longitudinal Evaluation of Mouse Hind Limb Bone Loss After Spinal Cord Injury using Novel, in vivo, Methodology

Spinal cord injury (SCI) is often accompanied by osteoporosis in the sublesional regions of the pelvis and lower extremities, leading to a higher frequency of fractures 1. As these fractures often occur in regions that have lost normal sensory function, the patient is at a greater risk of fracture-dependent pathologies, including death. SCI-dependent loss in both bone mineral density (BMD, grams/cm2) and bone mineral content (BMC, grams) has been attributed to mechanical disuse 2, aberrant neuronal signaling 3 and hormonal changes 4. The use of rodent models of SCI-induced osteoporosis can provide invaluable information regarding the mechanisms underlying the development of osteoporosis following SCI as well as a test environment for the generation of new therapies 5-7 (and reviewed in 8). Mouse models of SCI are of great interest as they permit a reductionist approach to mechanism-based assessment through the use of null and transgenic mice. While such models have provided important data, there is still a need for minimally-invasive, reliable, reproducible, and quantifiable methods in determining the extent of bone loss following SCI, particularly over time and within the same cohort of experimental animals, to improve diagnosis, treatment methods, and/or prevention of SCI-induced osteoporosis.
An ideal method for measuring bone density in rodents would allow multiple, sequential (over time) exposures to low-levels of X-ray radiation. This study describes the use of a new whole-animal scanner, the IVIS Lumina XR (Caliper Instruments) that can be used to provide low-energy (1-3 milligray (mGy)) high-resolution, high-magnification X-ray images of mouse hind limb bones over time following SCI. Significant bone density loss was seen in the tibiae of mice by 10 days post-spinal transection when compared to uninjured, age-matched control (na&iuml;ve) mice (13% decrease, p&lt;0.0005). Loss of bone density in the distal femur was also detectable by day 10 post-SCI, while a loss of density in the proximal femur was not detectable until 40 days post injury (7% decrease, p&lt;0.05). SCI-dependent loss of mouse femur density was confirmed post-mortem through the use of Dual-energy X-ray Absorptiometry (DXA), the current "gold standard" for bone density measurements. We detect a 12% loss of BMC in the femurs of mice at 40 days post-SCI using the IVIS Lumina XR. This compares favorably with a previously reported BMC loss of 13.5% by Picard and colleagues who used DXA analysis on mouse femurs post-mortem 30 days post-SCI 9. Our results suggest that the IVIS Lumina XR provides a novel, high-resolution/high-magnification method for performing long-term, longitudinal measurements of hind limb bone density in the mouse following SCI.

Longitudinal Evaluation of Mouse Hind Limb Bone Loss After Spinal Cord Injury using Novel, in vivo, Methodology

A longitudinal examination of bone loss in the femurs and tibiae of adult mice was performed following spinal cord injury using sequential low-dose X-ray scans. Tibia bone loss was detected throughout the study, while bone loss in the femur was not detected until 40 days post injury.

鼠标使用新型脊髓损伤的后肢骨质流失的纵向评价，在体内，方法论

Spinal cord injury (SCI) is often accompanied by osteoporosis in the sublesional regions of the pelvis and lower extremities, leading to a higher ...

科研

医学

Chronic Constriction of the Sciatic Nerve and Pain Hypersensitivity Testing in Rats

Chronic neuropathic pain, resulting from damage to the central or peripheral nervous system, is a prevalent and debilitating condition, affecting 7-18% of the population1,2. Symptoms include spontaneous (tingling, burning, electric-shock like) pain, dysaesthesia, paraesthesia, allodynia (pain resulting from normally non-painful stimuli) and hyperalgesia (an increased response to painful stimuli). The sensory symptoms are co-morbid with behavioural disabilities, such as insomnia and depression. To study chronic neuropathic pain several animal models mimicking peripheral nerve injury have been developed, one of the most widely used is Bennett and Xie's (1988) unilateral sciatic nerve chronic constriction injury (CCI)3 (Figure 1). Here we present a method for performing CCI and testing pain hypersensitivity.
CCI is performed under anaesthesia, with the sciatic nerve on one side exposed by making a skin incision, and cutting through the connective tissue between the gluteus superficialis and biceps femoris muscles. Four chromic gut ligatures are tied loosely around the sciatic nerve at 1 mm intervals, to just occlude but not arrest epineural blood flow. The wound is closed with sutures in the muscle and staples in the skin. The animal is then allowed to recover from surgery for 24 hrs before pain hypersensitivity testing begins.
For behavioural testing, rats are placed into the testing apparatus and are allowed to habituate to the testing procedure. The area tested is the mid-plantar surface of the hindpaw (Figure 2), which falls within the sciatic nerve distribution. Mechanical withdrawal threshold is assessed by mechanically stimulating both injured and uninjured hindpaws using an electronic dynamic plantar von Frey aesthesiometer or manual von Frey hairs4. The mechanical withdrawal threshold is the maximum pressure exerted (in grams) that triggers paw withdrawal. For measurement of thermal withdrawal latency, first described by Hargreaves et al (1988), the hindpaw is exposed to a beam of radiant heat through a transparent glass surface using a plantar analgesia meter5,6. The withdrawal latency to the heat stimulus is recorded as the time for paw withdrawal in both injured and uninjured hindpaws. Following CCI, mechanical withdrawal threshold, as well as thermal withdrawal latency in the injured paw are both significantly reduced, compared to baseline measurements and the uninjured paw (Figure 3). The CCI model of peripheral nerve injury combined with pain hypersensitivity testing provides a model system to investigate the effectiveness of potential therapeutic agents to modify chronic neuropathic pain. In our laboratory, we utilise CCI alongside thermal and mechanical sensitivity of the hindpaws to investigate the role of neuro-immune interactions in the pathogenesis and treatment of neuropathic pain.

Due to the simplicity of surgery and the robust behavioural outcome, chronic constriction of the sciatic nerve is one of the pre-eminent animal models of neuropathic pain. Within 24 hrs following surgery, pain hypersensitivity is established and can be quantitatively measured using a von Frey aesthesiometer (mechanical test) and plantar analgesia meter (thermal test).

慢性缩窄大鼠坐骨神经疼痛过敏测试

Chronic neuropathic pain, resulting from damage to the central or peripheral nervous system, is a prevalent and debilitating condition, affecting 7-18% of ...

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 ...

Evaluation of Respiratory Muscle Activation Using Respiratory Motor Control Assessment (RMCA) in Individuals with Chronic Spinal Cord Injury

During breathing, activation of respiratory muscles is coordinated by integrated input from the brain, brainstem, and spinal cord. When this coordination is disrupted by spinal cord injury (SCI), control of respiratory muscles innervated below the injury level is compromised1,2 leading to respiratory muscle dysfunction and pulmonary complications. These conditions are among the leading causes of death in patients with SCI3. Standard pulmonary function tests that assess respiratory motor function include spirometrical and maximum airway pressure outcomes: Forced Vital Capacity (FVC), Forced Expiratory Volume in one second (FEV1), Maximal Inspiratory Pressure (PImax) and Maximal Expiratory Pressure (PEmax)4,5. These values provide indirect measurements of respiratory muscle performance6. In clinical practice and research, a surface electromyography (sEMG) recorded from respiratory muscles can be used to assess respiratory motor function and help to diagnose neuromuscular pathology. However, variability in the sEMG amplitude inhibits efforts to develop objective and direct measures of respiratory motor function6. Based on a multi-muscle sEMG approach to characterize motor control of limb muscles7, known as the voluntary response index (VRI)8, we developed an analytical tool to characterize respiratory motor control directly from sEMG data recorded from multiple respiratory muscles during the voluntary respiratory tasks. We have termed this the Respiratory Motor Control Assessment (RMCA)9. This vector analysis method quantifies the amount and distribution of activity across muscles and presents it in the form of an index that relates the degree to which sEMG output within a test-subject resembles that from a group of healthy (non-injured) controls. The resulting index value has been shown to have high face validity, sensitivity and specificity9-11. We showed previously9 that the RMCA outcomes significantly correlate with levels of SCI and pulmonary function measures. We are presenting here the method to quantitatively compare post-spinal cord injury respiratory multi-muscle activation patterns to those of healthy individuals.

Evaluation of Respiratory Muscle Activation Using Respiratory Motor Control Assessment RMCA in Individuals with Chronic Spinal Cord Injury

The purpose of this publication is to present our original work on a multi-muscle surface electromyographic approach to quantitatively characterize respiratory muscle activation patterns in individuals with chronic spinal cord injury using vector-based analysis.

评价呼吸肌慢性脊髓损伤个人使用呼吸电机控制评估（RMCA）

During breathing, activation of respiratory muscles is coordinated by integrated input from the brain, brainstem, and spinal cord. When this coordination ...

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 ...

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 ...

Contrast Enhanced Ultrasound Imaging for Assessment of Spinal Cord Blood Flow in Experimental Spinal Cord Injury

Reduced spinal cord blood flow (SCBF) (i.e., ischemia) plays a key role in traumatic spinal cord injury (SCI) pathophysiology and is accordingly an important target for neuroprotective therapies. Although several techniques have been described to assess SCBF, they all have significant limitations. To overcome the latter, we propose the use of real-time contrast enhanced ultrasound imaging (CEU). Here we describe the application of this technique in a rat contusion model of SCI. A jugular catheter is first implanted for the repeated injection of contrast agent, a sodium chloride solution of sulphur hexafluoride encapsulated microbubbles. The spine is then stabilized with a custom-made 3D-frame and the spinal cord dura mater is exposed by a laminectomy at ThIX-ThXII. The ultrasound probe is then positioned at the posterior aspect of the dura mater (coated with ultrasound gel). To assess baseline SCBF, a single intravenous injection (400 &#181;l) of contrast agent is applied to record its passage through the intact spinal cord microvasculature. A weight-drop device is subsequently used to generate a reproducible experimental contusion model of SCI. Contrast agent is re-injected 15 min following the injury to assess post-SCI SCBF changes. CEU allows for real time and in-vivo assessment of SCBF changes following SCI. In the uninjured animal, ultrasound imaging showed uneven blood flow along the intact spinal cord. Furthermore, 15 min post-SCI, there was critical ischemia at the level of the epicenter while SCBF remained preserved in the more remote intact areas. In the regions adjacent to the epicenter (both rostral and caudal), SCBF was significantly reduced. This corresponds to the previously described &#8220;ischemic penumbra zone&#8221;. This tool is of major interest for assessing the effects of therapies aimed at limiting ischemia and the resulting tissue necrosis subsequent to SCI.

Contrast Enhanced Ultrasound imaging is a reliable in-vivo tool for quantifying spinal cord blood flow in an experimental rat spinal cord injury model. This paper contains a comprehensive protocol for application of this technique in association with a contusion model of thoracic spinal cord injury.

超声造影成像脊髓血流量的评估实验脊髓损伤

Reduced spinal cord blood flow (SCBF) (i.e., ischemia) plays a key role in traumatic spinal cord injury (SCI) pathophysiology and is accordingly an ...