1。患者准备<ol><li>被称为肿瘤医学部为基准的神经兴奋性测试之前开始对化疗的患者。 </li><li>必须确定病人适宜的兴奋性测试。患者应排除在外，如果他们有一个历史的或基线周围神经病变的神经电生理证据，已收到之前毒性的化疗治疗，或有任何禁忌的兴奋性测试。 </li></ol> 2。轴突兴奋程序<ol><li>承担对正中神经的感觉和运动神经的兴奋性协议，使用半自动化的电脑系统QTracS（神经病学研究所，英国女王广场，），一个孤立的线性双极恒流刺激（Digitimer，韦林花园城，英国）和放大器（蓝宝石IIA，Medelec，英国）。 </li><li>准备在手腕和前臂皮肤表面与磨料的凝胶或垫，以减少皮肤性，应用酒精擦拭。 </li><li>准备录制现场，马达录音与非极化电极置于拇短展肌和参考电极4厘米的远端记录复合肌肉动作电位（的CMap）的腹部肌肉。 </li><li>为感官录音准备录制现场 - 用环形电极分别放置在近端和远端指间关节的记录和参考电极，记录化合物的感官动作电位（CSAPs）。 </li><li>放置一个电中性地球板块在掌心，用导电胶。 </li><li>在录制设置的电气噪声应尽可能去除，使用1哄骗50/60 Hz噪声消除（任务科学仪器，北温哥华，加拿大）。 </li><li>刺激正中神经在腕部。刺激部位应选择门槛最低的网站，使用一个重新定位的双极电极和随后的非-Polarizable电极。 </li><li>阳极电极应放在刺激电极从超过骨近端10厘米。 </li><li>在刺激整个测试现场监测温度，确保温度超过32°C </li></ol> 3。轴突兴奋性协议<ol><li>逐步增加的刺激，直到反应是最大的，并且不增加刺激的强度进一步增加时，记录刺激响应曲线。 </li><li>阈值跟踪的目标幅度自动设置为30％-40％的幅度最大，相应的陡斜坡上的刺激 - 反应曲线面积。 </li><li>每博斯托克等人 ，1998年法，电流阈值的变化需要实现的目标幅度在线跟踪。 </li><li>记录包括多个兴奋阈值电紧张（TE），回收周期（RC）和电流阈值（的I / V）的关系参数，描述在基尔南等人，2000年和基尔南等。，2001年。 </li><li>阈值电紧张进行评估使用100ms的阈极化电流，极化电流设置为控制阈值的±40％（ 图1）。在阈值电流的变化，需要保持目标响应的幅度后，两德和超极化记录。阈值电紧张提供一个节间的电导和膜电位的评估与反应中的极化方向，在偏光强烈脉冲膜电位（MS 90-100）结束。 </li><li>配对脉冲范例（ 图2），使用初始超强空调，在不同的时间间隔（从2.5毫秒到200毫秒）测试刺激刺激经济复苏周期评估。超强刺激，更难以产生后续反应，称为“耐火度”，反映失活电压-Gated钠离子通道。不应期之后，发生了便利的期间为superexcitability。 </li><li>电流阈值之间的关系进行评估，使用偏光200毫秒从+50％-100％的阈值电流强度变化。 </li></ol> 4。病人的评估<ol><li>使用这些技术，患者整个化疗治疗急性和纵向评估。评估急性毒性，患者接受治疗的48小时内返回化疗后评估。 </li><li>检查慢性神经毒性，化疗输液之前采取的评估是纵向比较，整个治疗周期。 </li><li>此外轴突兴奋性测试，传统的临床分级尺度应采用通用标准评估化疗引起的神经毒性，包括国家癌症研究所 - 不良事件神经病感觉量表，共有病变分数和帕特ient报告结果评估。 </li></ol> 5。分析和解释<ol><li>为了确定急性毒性，结果进行了比较前和化疗后的治疗。评估神经功能的纵向变化的发展，在治疗结果进行了比较。评估的关键参数包括耐火度，superexcitability，在阈值电紧张（极化90-100毫秒）阈值的变化范围，除了传统的参数，如峰值振幅和延迟。 </li><li>评估在治疗的兴奋性参数的整体变化，复合兴奋得分计算。总结，从最初到最终处理的superexcitability，耐火度以及阈值电紧张（极化90-100毫秒） - - 三个参数的变化，给一个整体的变化的标志。 </li></ol> 6。代表结果兴奋的结果的例子在拍拍奥沙利铂治疗ient提供。立即奥沙利铂注射后，在感觉和运动神经的兴奋性急性发展变化，暗示功能的钠离子通道10 -13的发展。然而，在多兴奋的参数显着的变化逐步发展跨奥沙利铂治疗，只有在感觉神经轴突与运动神经元轴突的影响（ 图3），反映普遍感觉轴索损伤和膜电位变化。这种模式匹配的慢性奥沙利铂神经毒性症状的临床表现。在感觉神经轴突兴奋性的改变之前的峰值幅度减少使用传统的神经传导技术评估，并建议轴突兴奋的技术，可提供敏感的评估工具，为早期奥沙利铂神经毒性。 <img alt="图1" src="/files/ftp_upload/3439/3439fig1.jpg" /> 图1。 </st荣毅仁&gt;阈值电紧张，描绘偏振极化方向的电流（100毫秒），延长阈波形绘制在底部象限（蓝色）和极化方向绘制在右上腹（红色）。下面是激励波形产生的阈值电紧张反应。 <img alt="图2" src="/files/ftp_upload/3439/3439fig2.jpg" /> 图2。恢复周期的兴奋性，降低兴奋期（耐火度）3毫秒超强刺激后的兴奋性增高（superexcitability）期间，在5调峰证明后冲动传导的兴奋性变化的特征序列， -7毫秒，随后降低兴奋性（subexcitability）。成对的脉冲范式刺激协议插图。 <img alt="图3" src="/files/ftp_upload/3439/3439fig3.jpg" /> 无花果由图3。基线记录 ​​显示在白色显示的黑色和治疗后的录音，奥沙利铂治疗4-6个月后，在奥沙利铂治疗的患者感觉轴突兴奋性的改变。这些变化被认为是反映了广泛的轴索损伤和膜电位变化。在肿瘤设置兴奋设置的图片显示在左侧。 <a href="http://www.jove.com/files/ftp_upload/3439/3439fig3large.jpg" target="_blank">点击这里查看大图</a> 。

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	<li>Hausheer, F. H., Schilsky, R. L., Bain, S., Berghorn, E. J., Lieberman, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnosis,+management,+and+evaluation+of+chemotherapy-induced+peripheral+neuropathy.">Diagnosis, management, and evaluation of chemotherapy-induced peripheral neuropathy.</a> Semin. Oncol. 33, 15-49 (2008).</li><li>Park, S. B., Krishnan, A. V., Lin, C. S., Goldstein, D., Friedlander, M., Kiernan, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+underlying+chemotherapy-induced+neurotoxicity+and+the+potential+for+neuroprotective+strategies.">Mechanisms underlying chemotherapy-induced neurotoxicity and the potential for neuroprotective strategies.</a> Curr. Med. Chem. 15, 3081-3094 (2008).</li><li>Park, S. B., Lin, C. S., Krishnan, A. 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我们什么都没有透露。

化疗引起的神经病变，是一种治疗癌症的严重的副作用，这可能会影响疗程，并产生长期的病人残疾。有一个缺乏敏感和客观的评估措施，专门测量化疗治疗的患者的神经功能障碍。轴突兴奋性技术的临床发展提供了有益的和预测的信息，评估化疗引起的神经毒性。通过提供有关离子通道的功能，静息电位和轴突膜功能的信息，这些技术使在接受化疗的癌症患者的相关性轴索功能障碍的病理生理过程的洞察力。此外，轴突兴奋的技术已被证明是可行的，在临床肿瘤学设置，可在5-10分钟内完成一个单一的测试。 在奥沙利铂治疗的患者中，轴突兴奋的技术提供一个敏感的生物标志物，使患者的早期识别，在严重的神经毒性的风险。在已经发生了比较传统的神经传导研究确定奥沙利铂引起神经损伤，轴索损失后，轴突兴奋的研究提供了神经功能障碍的预测指标前轴突损失。因此，可利用轴突兴奋性研究提供潜在的神经保护策略的临床试验，神经功能评估，客观地确定神经保护作用。

<table border="1"><tbody><tr><td> 设备和材料 </td><td> 公司 </td></tr><tr><td> QTracS方案</td><td> digitimer，神经病学研究所，英国女王广场， </td></tr><tr><td> DS5孤立的线性双极型恒流刺激</td><td> digitimer </td></tr><tr><td>蓝宝石IIA级放大器</td><td> medelec </td></tr><tr><td>哄骗50/60 Hz噪声消除</td><td>追求科学仪器</td></tr><tr><td>非极化电极</td><td> unomedical </td></tr><tr><td>电中性地球板块</td><td> unomedical </td></tr></tbody></table>

nerve excitability assessment in chemotherapy-induced neurotoxicity

化疗引起的神经毒性，是一种治疗癌症，其中发生的一些最常用的化疗1,2严重的后果。化疗引起的周围神经病变产生于四肢麻木和感觉异常的症状，并可能进步与精细动作技能和行走困难，从而导致功能障碍。除了产生令人不安的症状，化疗引起的神经病变可导致减少剂量或停止治疗早期治疗成功限制。神经症状可能会持续长期，否则预后良好的病人留下永久性神经损伤。由于化疗更经常地利用作为一种预防性措施，存活率增加，长期持久和显着的神经毒性的重要性将会增加。 有没有既定的神经保护或治疗方案和缺乏敏感的评估方法。 appropr神经毒性的的滴管评估将作为预后因子和神经保护剂适用于未来的审判端点的关键。电流的方法来评估化疗引起的神经病变的严重程度，利用临床为基础的分级，这已被证明缺乏敏感性改变和观察员间的客观性4尺度。传统的神经传导研究提供有关复合动作电位幅度和传导速度，这是相对非具体措施和不提供洞察到离子通道的功能或静息膜电位的信息。因此，以前的研究已经证明，传统的神经传导不敏感，化疗引起的神经毒性4-6早期变化。相比较而言，神经兴奋性研究利用阈值跟踪技术已开发，使体内的离子通道，泵和热交换器的评估，在大的人类髓轴突7-9。 已经建立了神经兴奋性技术作为一种工具，研究开发和化疗引起的神经毒性10-13严重性。组成的兴奋性参数的数量，可用于神经兴奋性研究，以评估急性毒性产生后立即输液和慢性的，累积的神经毒性的发展。神经兴奋性技术在临床上是可行的，每个只有5至10分钟才能完成测试。神经兴奋设备很容易商业化，并已制定便携式系统，可以使患者在输液中心的设置原位测试。此外，这些技术可以适应多个化疗使用。 在与使用，主要用于大肠癌，化疗奥沙利铂治疗的患者，神经兴奋性技术提供了一种方法，以确定病人T-慢性神经病发病前的神经毒性的风险。神经兴奋性的研究发现急性钠离子通道在电机和10-13感觉轴突的发展。重要的是，谁表现出兴奋性的改变，在早期治疗的患者随后更可能患上中度至严重 ​​的神经毒性11。然而，在治疗中，引人注目的纵向变化进行鉴定，只有在感觉轴突能够预测临床神经功能结果，80％的患者10。这些变化表现出不同的模式，以敏锐地看到奥沙利输液，最有可能反映了发展的显着性轴索损伤和感觉神经膜电位变化，纵向发展在奥沙利铂治疗10。在早期治疗，减少神经功能的常规措施之前，任何显着的异常，这表明前citability参数可能提供了一个敏感的生物标志物。

Watch this Scientific Journal Video about Nerve Excitability Assessment in Chemotherapy-induced Neurotoxicity at JoVE.com

Nerve Excitability Assessment in Chemotherapy-induced Neurotoxicity

这个抽象描述了一种新的方法来评估神经毒性的发展，在接受化疗治疗的患者。而传统的评估方法检测神经功能的早期变化的能力有限，神经兴奋性技术在严重的神经毒性和洞察到的病理生理的风险提供患者的早期识别。

化疗引起的毒性神经的兴奋性评估

Chemotherapy-induced neurotoxicity is a serious consequence of cancer treatment, which occurs with some of the most commonly used chemotherapies1,2. ...

nerve-excitability-assessment-in-chemotherapy-induced-neurotoxicity

Research

JoVE Journal

Neuroscience

18.0K 次观看.  University of New South Wales. 这个抽象描述了一种新的方法来评估神经毒性的发展，在接受化疗治疗的患者。而传统的评估方法检测神经功能的早期变化的能力有限，神经兴奋性技术在严重的神经毒性和洞察到的病理生理的风险提供患者的早期识别。

视频: Nerve Excitability Assessment in Chemotherapy-induced Neurotoxicity

Reproducible Mouse Sciatic Nerve Crush and Subsequent Assessment of Regeneration by Whole Mount Muscle Analysis

Regeneration in the peripheral nervous system (PNS) is widely studied both for its relevance to human disease and to understand the robust regenerative response mounted by PNS neurons thereby possibly illuminating the failures of CNS regeneration1. Sciatic nerve crush (axonotmesis) is one of the most common models of peripheral nerve injury in rodents2. Crushing interrupts all axons but Schwann cell basal laminae are preserved so that regeneration is optimal3,4. This allows the investigator to study precisely the ability of a growing axon to interact with both the Schwann cell and basal laminae4. Rats have generally been the preferred animal models for experimental nerve crush. They are widely available and their lesioned sciatic nerve provides a reasonable approximation of human nerve lesions5,4. Though smaller in size than rat nerve, the mouse nerve has many similar qualities. Most importantly though, mouse models are increasingly valuable because of the wide availability of transgenic lines now allows for a detailed dissection of the individual molecules critical for nerve regeneration6, 7. Prior investigators have used multiple methods to produce a nerve crush or injury including simple angled forceps, chilled forceps, hemostatic forceps, vascular clamps, and investigator-designed clamps8,9,10,11,12. Investigators have also used various methods of marking the injury site including suture, carbon particles and fluorescent beads13,14,1. We describe our method to obtain a reproducibly complete sciatic nerve crush with accurate and persistent marking of the crush-site using a fine hemostatic forceps and subsequent carbon crush-site marking. As part of our description of the sciatic nerve crush procedure we have also included a relatively simple method of muscle whole mount we use to subsequently quantify regeneration.

In this report we describe a method to crush mouse sciatic nerve. This method uses readily available hemostatic forceps and easily and reproducibly produces complete sciatic nerve crush. In addition, we describe a method to prepare muscle whole mounts suitable for analysis of nerve regeneration after sciatic nerve crush.

重复性小鼠坐骨神经挤压和再生的后续评估整装肌肉分析

Regeneration in the peripheral nervous system (PNS) is widely studied both for its relevance to human disease and to understand the robust regenerative ...

科研

神经科学

Assessment of Neuromuscular Function Using Percutaneous Electrical Nerve Stimulation

Percutaneous electrical nerve stimulation is a non-invasive method commonly used to evaluate neuromuscular function from brain to muscle (supra-spinal, spinal and peripheral levels). The present protocol describes how this method can be used to stimulate the posterior tibial nerve that activates plantar flexor muscles. Percutaneous electrical nerve stimulation consists of inducing an electrical stimulus to a motor nerve to evoke a muscular response. Direct (M-wave) and/or indirect (H-reflex) electrophysiological responses can be recorded at rest using surface electromyography. Mechanical (twitch torque) responses can be quantified with a force/torque ergometer. M-wave and twitch torque reflect neuromuscular transmission and excitation-contraction coupling, whereas H-reflex provides an index of spinal excitability. EMG activity and mechanical (superimposed twitch) responses can also be recorded during maximal voluntary contractions to evaluate voluntary activation level. Percutaneous nerve stimulation provides an assessment of neuromuscular function in humans, and is highly beneficial especially for studies evaluating neuromuscular plasticity following acute (fatigue) or chronic (training/detraining) exercise.

We present a protocol to assess changes in neuromuscular function. Percutaneous electrical nerve stimulation is a non-invasive method that evokes muscular responses. Electrophysiological and mechanical properties of these responses permit the evaluation of neuromuscular function from brain to muscle (supra-spinal, spinal and peripheral levels).

神经肌肉功能的应用经皮神经电刺激评估

Percutaneous electrical nerve stimulation is a non-invasive method commonly used to evaluate neuromuscular function from brain to muscle (supra-spinal, ...

Microglia as a Surrogate Biosensor to Determine Nanoparticle Neurotoxicity

Nanoparticles found in air pollutants can alter neurotransmitter profiles, increase neuroinflammation, and alter brain function. Therefore, the assay described here will aid in elucidating the role of microglia in neuroinflammation and neurodegenerative diseases. The use of microglia, resident immune cells of the brain, as a surrogate biosensor provides novel insight into how inflammatory responses mediate neuronal insults. Here, we utilize an immortalized murine microglial cell line, designated BV2, and describe a method for nanoparticle exposure using silver nanoparticles (AgNPs) as a standard. We describe how to expose microglia to nanoparticles, how to remove nanoparticles from supernatant, and how to use supernatant from activated microglia to determine toxicity, using hypothalamic cell survival as a measure. Following AgNP exposure, BV2 microglial activation was validated using a tumor necrosis factor alpha (TNF-&#945;) enzyme linked immunosorbent assay (ELISA). The supernatant was filtered to remove the AgNP and to allow cytokines and other secreted factors to remain in the conditioned media. Hypothalamic cells were then exposed to supernatant from AgNP activated microglia and survival of neurons was determined using a resazurin-based fluorescent assay. This technique is useful for utilizing microglia as a surrogate biomarker of neuroinflammation and determining the effect of neuroinflammation on other cell types.

Microglia (immune cells of the brain), are used as a surrogate biosensor to determine how nanoparticles influence neurotoxicity. We describe a series of experiments designed to assay microglial response to nanoparticles and exposure of hypothalamic neurons to supernatant from activated microglia to determine neurotoxicity.

小胶质细胞作为替代生物传感器确定纳米颗粒神经毒性

Nanoparticles found in air pollutants can alter neurotransmitter profiles, increase neuroinflammation, and alter brain function. Therefore, the assay ...

In Utero Electroporation Approaches to Study the Excitability of Neuronal Subpopulations and Single-cell Connectivity

The nervous system is composed of an enormous range of distinct neuronal types. These neuronal subpopulations are characterized by, among other features, their distinct dendritic morphologies, their specific patterns of axonal connectivity, and their selective firing responses. The molecular and cellular mechanisms responsible for these aspects of differentiation during development are still poorly understood.
Here, we describe combined protocols for labeling and characterizing the structural connectivity and excitability of cortical neurons. Modification of the in utero electroporation (IUE) protocol allows the labeling of a sparse population of neurons. This, in turn, enables the identification and tracking of the dendrites and axons of individual neurons, the precise characterization of the laminar location of axonal projections, and morphometric analysis. IUE can also be used to investigate changes in the excitability of wild-type (WT) or genetically modified neurons by combining it with whole-cell recording from acute slices of electroporated brains. These two techniques contribute to a better understanding of the coupling of structural and functional connectivity and of the molecular mechanisms controlling neuronal diversity during development. These developmental processes have important implications on axonal wiring, the functional diversity of neurons, and the biology of cognitive disorders.

In Utero Electroporation Approaches to Study the Excitability of Neuronal Subpopulations and Single-cell Connectivity

This manuscript provides protocols that use in utero electroporation (IUE) to describe the structural connectivity of neurons at the single-cell level and the excitability of fluorescently labeled neurons. Histology is used to characterize dendritic and axonal projections. Whole-cell recording in acute slices is used to investigate excitability.

在子宫内电途径研究神经元亚群的兴奋性和单细胞连接

The nervous system is composed of an enormous range of distinct neuronal types. These neuronal subpopulations are characterized by, among other features, ...

In Vivo Electrophysiological Measurement of the Rat Ulnar Nerve with Axonal Excitability Testing

Electrophysiology enables the objective assessment of peripheral nerve function in vivo. Traditional nerve conduction measures such as amplitude and latency detect chronic axon loss and demyelination, respectively. Axonal excitability techniques &#34;by threshold tracking&#34; expand upon these measures by providing information regarding the activity of ion channels, pumps and exchangers that relate to acute function and may precede degenerative events. As such, the use of axonal excitability in animal models of neurological disorders may provide a useful in vivo measure to assess novel therapeutic interventions. Here we describe an experimental setup for multiple measures of motor axonal excitability techniques in the rat ulnar nerve.
The animals are anesthetized with isoflurane and carefully monitored to ensure constant and adequate depth of anesthesia. Body temperature, respiration rate, heart rate and saturation of oxygen in the blood are continuously monitored. Axonal excitability studies are performed using percutaneous stimulation of the ulnar nerve and recording from the hypothenar muscles of the forelimb paw. With correct electrode placement, a clear compound muscle action potential that increases in amplitude with increasing stimulus intensity is recorded. An automated program is then utilized to deliver a series of electrical pulses which generate 5 specific excitability measures in the following sequence: stimulus response behavior, strength duration time constant, threshold electrotonus, current-threshold relationship and the recovery cycle.
Data presented here indicate that these measures are repeatable and show similarity between left and right ulnar nerves when assessed on the same day. A limitation of these techniques in this setting is the effect of dose and time under anesthesia. Careful monitoring and recording of these variables should be undertaken for consideration at the time of analysis.

In Vivo Electrophysiological Measurement of the Rat Ulnar Nerve with Axonal Excitability Testing

Axonal excitability techniques provide a powerful tool to examine pathophysiology and biophysical changes that precede irreversible degenerative events. This manuscript demonstrates the use of these techniques on the ulnar nerve of anesthetized rats.

在体内轴突兴奋性试验对大鼠尺神经的电生理测量

Electrophysiology enables the objective assessment of peripheral nerve function in vivo. Traditional nerve conduction measures such as amplitude and ...

Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential

Recently, the isolated-check visual evoked potential (icVEP) technique was designed and has been reported to detect glaucomatous damage earlier and faster. It creates low spatial frequency/high temporal frequency bright stimuli and records cortical activity initiated primarily by afferents in the magnocellular ON pathway. This pathway contains neurons with larger volumes and axonal diameters, and it is preferentially damaged in early glaucoma, which can result in visual field loss. The study presented here uses standard operative procedures (SOP) of icVEP to obtain reliable results. It can detect visual function loss using a signal-to-noise ratio (SNR) corresponding to the defects of retinal nerve fiber layer (RNFL) in early stage open-angle glaucoma (OAG). A setting of 10 Hz and condition of 15% positive-contrast (bright) are selected to differentiate OAG patients and control subjects, with each check containing eight runs. Each run persists for 2 s (for 20 total cycles). A flowchart is constructed, which consists of pupil size and intraocular pressure over a 30 min rest period before each examination. Additionally, the testing order of eyes is performed to obtain reliable electroencephalographic signals. VEPs are recorded and analyzed automatically by software, and SNRs are derived based on a multivariate statistic. An SNR of &#8804; 1 is considered abnormal. A receiver-operating-characteristic (ROC) curve is applied to analyze the accuracy of group classification. Then, the SOP is applied in a cross-sectional study, showing that icVEP can detect glaucomatous visual function abnormality in the central visual field in the form of SNR. This value also correlates with the thickness thinning of RNFL and produces high classification accuracy for early stage OAG. Thus, it serves as a useful and objective diagnostic technology for the early detection of glaucoma.

The isolated-check visual evoked potential (icVEP) method is implemented here to assess the magnocellular ON pathway that is initially damaged in glaucoma. The study shows standard operative procedures using icVEP to obtain reliable results. It is proved to serve as a useful objective diagnosing technology for the early detection of glaucoma.

通过隔离检查视觉诱发潜力评估患者早期开放角青光眼

Recently, the isolated-check visual evoked potential (icVEP) technique was designed and has been reported to detect glaucomatous damage earlier and ...

Purification of Fibroblasts and Schwann Cells from Sensory and Motor Nerves in Vitro

The principal cells in the peripheral nervous system are the Schwann cells (SCs) and the fibroblasts. Both these cells distinctly express the sensory and motor phenotypes involved in different patterns of neurotrophic factor gene expression and other biological processes, affecting nerve regeneration. The present study has established a protocol to obtain highly purified rat sensory and motor SCs and fibroblasts more rapidly. The ventral root (motor nerve) and the dorsal root (sensory nerve) of neonatal rats (7-days-old) were dissociated and the cells were cultured for 4-5 days, followed by isolation of sensory and motor fibroblasts and SCs by combining differential digestion and differential adherence methods sequentially. The results of immunocytochemistry and flow cytometry analyses showed that the purity of the sensory and motor SCs and fibroblasts were &#62;90%. This protocol can be used to obtain a large number of sensory and motor fibroblasts/SCs more rapidly, contributing to the exploration of sensory and motor nerve regeneration.

Here, we present a method to purify fibroblasts and Schwann cells from sensory and motor nerves in vitro.

从体外感觉和运动神经中纯化成纤维细胞和施万细胞

The principal cells in the peripheral nervous system are the Schwann cells (SCs) and the fibroblasts. Both these cells distinctly express the sensory and ...

Multifactorial Assessment of Motor Behavior in Rats after Unilateral Sciatic Nerve Crush Injury

The induction of a peripheral nerve injury is a widely used method in neuroscience for the assessment of repair and pain mechanisms among others. In addition, in the research field of movement disorders, sciatic crush injury has been employed to trigger a dystonia-like phenotype in genetically predisposed DYT-TOR1A rodent models of dystonia. To achieve consistent, reproducible and comparable results after a sciatic nerve crush injury, a standardized method for inducing the nerve crush is essential, in addition to a standardized phenotypical characterization. Attention must be paid not only to the specific assortment of behavioral tests, but also to the technical requirements, the correct execution and consecutive data analysis. This protocol describes in detail how to perform a sciatic nerve crush injury and provides a behavioral test battery for the assessment of motor deficits in rats that includes the open field test, the CatWalk XT gait analysis, the beam walking task, and the ladder rung walking task.

We provide a protocol for the assessment of motor behavior via a behavioral test battery in rats after sciatic nerve crush injury.

单边坐骨神经粉碎损伤后大鼠运动行为的多因素评估

The induction of a peripheral nerve injury is a widely used method in neuroscience for the assessment of repair and pain mechanisms among others. In ...

Brain Ventricular Microinjections of Lipopolysaccharide into Larval Zebrafish to Assess Neuroinflammation and Neurotoxicity

Neuroinflammation is a key player in various neurological disorders, including neurodegenerative diseases. Therefore, it is of great interest to research and develop alternative in vivo neuroinflammation models to understand the role of neuroinflammation in neurodegeneration. In this study, a larval zebrafish model of neuroinflammation mediated by ventricular microinjection of lipopolysaccharide (LPS) to induce an immune response and neurotoxicity was developed and validated. The transgenic zebrafish lines elavl3:mCherry, ETvmat2:GFP, and mpo:EGFP were used for real-time quantification of brain neuron viability by fluorescence live imaging integrated with fluorescence intensity analysis. The locomotor behavior of zebrafish larvae was recorded automatically using a video-tracking recorder. The content of nitric oxide (NO), and the mRNA expression levels of inflammatory cytokines including interleukin-6 (IL-6), interleukin-1&#946; (IL-1&#946;), and human tumor necrosis factor &#945; (TNF-&#945;) were investigated to assess the LPS-induced immune response in the larval zebrafish head. At 24 h after the brain ventricular injection of LPS, loss of neurons and locomotion deficiency were observed in zebrafish larvae. In addition, LPS-induced neuroinflammation increased NO release and the mRNA expression of IL-6, IL-1&#946;, and TNF-&#945; in the head of 6 days post fertilization (dpf) zebrafish larvae, and resulted in the recruitment of neutrophils in the zebrafish brain. In this study, injection of zebrafish with LPS at a concentration of 2.5-5 mg/mL at 5 dpf was determined as the optimum condition for this pharmacological neuroinflammation assay. This protocol presents a new, quick, and efficient methodology for brain ventricle microinjection of LPS to induce LPS-mediated neuroinflammation and neurotoxicity in a zebrafish larva, which is useful for studying neuroinflammation and could also be used as a high-throughput in vivo drug screening assay.

This protocol demonstrates the microinjection of lipopolysaccharide into the brain ventricular region in a zebrafish larval model to study the resulting neuroinflammatory response and neurotoxicity.

脑室微注射脂多糖到斑马鱼幼虫中以评估神经炎症和神经毒性

Neuroinflammation is a key player in various neurological disorders, including neurodegenerative diseases. Therefore, it is of great interest to research ...

Assessing Corticospinal Excitability During Goal-Directed Reaching Behavior

Reaching is a widely studied behavior in motor physiology and neuroscience research. While reaching has been examined using a variety of behavioral manipulations, there remain significant gaps in the understanding of the neural processes involved in reach planning, execution, and control. The novel approach described here combines a two-dimensional reaching task with transcranial magnetic stimulation (TMS) and concurrent electromyography (EMG) recording from multiple muscles. This method allows for the noninvasive detection of corticospinal activity at precise time points during the unfolding of reaching movements. The example task code includes a delayed response reaching task with two possible targets displayed &#177; 45&#176; off the midline. Single pulse TMS is delivered on the majority of task trials, either at the onset of the preparatory cue (baseline) or 100 ms prior to the imperative cue (delay). This sample design is suitable for investigating changes in corticospinal excitability during reach preparation. The sample code also includes a visuomotor perturbation (i.e., cursor rotation of &#177; 20&#176;) to investigate the effects of adaptation on corticospinal excitability during reach preparation. The task parameters and TMS delivery can be adjusted to address specific hypotheses about the state of the motor system during reaching behavior. In the initial implementation, motor evoked potentials (MEPs) were successfully elicited on 83% of TMS trials, and reach trajectories were recorded on all trials.

Reaching is a fundamental skill that allows humans to interact with the environment. Several studies have aimed to characterize reaching behavior using a variety of methodologies. This paper offers an open-source application of transcranial magnetic stimulation to assess the state of corticospinal excitability in humans during reaching task performance.

评估目标导向到达行为期间的皮质脊髓兴奋性

Reaching is a widely studied behavior in motor physiology and neuroscience research. While reaching has been examined using a variety of behavioral ...