This study was supported by NeuralStem, Inc., and Johns Hopkins Project RESTORE.

注：所有动物的程序批准了美国约翰霍普金斯大学动物护理和使用委员会。麻醉机需要每年检查和校准是必要的。 1.麻醉和定位<ol><li>麻醉。 <ol><li>执行麻醉下用2-3％异氟烷所有的外科手术。确认麻醉通过脚趾捏和呼吸速率适当的水平。检查该大鼠不响应于脚趾捏退缩。 注：退缩表明麻醉是为时已晚，并且可能需要在开始之前再麻醉或更高浓度的异氟醚。的呼吸率小于1呼吸每2秒的速度太慢，指示麻醉太高，并且可能需要在异氟烷浓度的减轻。 </li><li>确保必要的动物，以避免在操作过程中的头部运动。将利多卡因对手术眼睛的下降。使用人工泪液，每10分钟，以防止干燥，而在麻醉下。给根据需要注射的0.01毫克/千克SC预可操作然后每6-8小时丁丙诺啡。 </li></ol></li><li>定位。 <ol><li>将老鼠变成一个立体框架和一个加热垫保暖。湿头皮毛皮用酒精小心地避免暴露在眼前。使用无菌的工具和无菌技术，以减少手术后感染的风险。 </li></ol></li></ol> 2.眼控<ol><li>放置4-0缝合线在横向和结膜有足够的缝合比分扳成允许牵引温柔。 </li></ol> 3.解剖<ol><li>初步解剖。 <ol><li>使一〜1英寸切口，在皮肤上覆使用大小为10解剖刀， 如图1中的轨道脊。缩回皮肤和下面的筋膜并小心剖析远离筋膜。为了防止出血过多进入手术，避免削减血管解剖时筋膜。使用PL的战略一杆进洞棉花提示，以提供止血。 </li></ol></li><li>更深层次的剖析。 注：随着对拉动结膜眼潦倒插槽温柔的牵引，眶上肌肉就会映入眼帘。为了揭露视神经，这种肌肉必须进行切割和眶脂肪去除。脂肪可以被丢弃，并应在注射后不能被替换。从这点来说，视神经筋膜应尽可能视神经本身束可见，随着包裹在硬脑膜血管（ 图1）。 <ol><li>让使用手术刀或31计斜面针头刺入做创伤小一小切口硬脑膜。 </li></ol></li></ol> 4.移取喷油器<ol><li>拉玻璃微量吸管到直径为50-100微米。以提供稳定性，装入微量上一个显微和附加到Hamilton注射器连接于输注泵。 </li><li>拉起珠（或干细胞）重组在0.5-1.0微升卷成随着甲基蓝溶液之前和之后的0.5微升体积逆行微量。 注意：一个输注率设定为每分钟0.5-2微升防止外伤视神经。 </li></ol> 5.注射<ol><li>降低微量的前端到视神经正上方的缺口硬脑膜。 注：在玻璃尖端的微小的，但轻快运动进入视神经导致损害最小。作为输液泵开始时，甲基蓝染料应突出注入视神经的面积。染料应视神经内不会泄漏出在蛛网膜下腔保持本地化。 </li><li>遵循甲基蓝的第二频带，以确定何时所述干细胞注射完成并打开输液泵关闭甲基蓝的第二剂量注入。保持微量仍然视神经内，2分钟，每1微升体积注入，以防止高在撤离的微压顶出。 注：另一种方法是将枪头连接到一个充有空气的注射器可手动操纵。无论哪种方式，避免用力过大，以减少损害视神经。我们建议注入不超过2微升体积的在每个视神经。 </li></ol> 6.跟进<ol><li>即时。 <ol><li>当注射完成后，取出微管以及用于提供止血棉的任何提示。缝合皮肤用3-0丝线和删除结膜缝合。 </li><li>保持温暖的老鼠在一个加热垫，直到他们从麻醉中出现。不要让动物无人值守，直到它已经恢复了意识足以维持胸骨斜卧。不返回已经历手术给其他动物的公司，直到完全恢复的动物。 </li><li>如果动物表现出疼痛的迹象，包括过度嗜睡，运动失调，或吃力的呼吸克，适当管理与镇痛丁丙诺啡肌肉注射（0.05毫克/千克），最多每日三次。 </li></ol></li><li>长期。 <ol><li>在接下来的24-48小时，观察大鼠进行手术的并发症，包括从伤口肿胀或分泌物或疼痛等体征如的发声，弯腰驼背的样子，不修饰，或不思饮食。考虑与兽医或伦理安乐死进行必要的磋商。 </li></ol></li></ol>

<ol>
	<li>Dahlmann-Noor, A., Vijay, S., Jayaram, H., Limb, A., Khaw, P. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+approaches+and+future+prospects+for+stem+cell+rescue+and+regeneration+of+the+retina+and+optic+nerve.">Current approaches and future prospects for stem cell rescue and regeneration of the retina and optic nerve.</a> Canadian journal of ophthalmology Journal canadien d'ophtalmologie. 45 (4), 333-341 (2010).</li><li>Quigley, H. A., Iglesia, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stem+cells+to+replace+the+optic+nerve.">Stem cells to replace the optic nerve.</a> Eye. 18 (11), 1085-1088 (2004).</li><li>Ghaffarieh, A., Levin, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optic+nerve+disease+and+axon+pathophysiology.">Optic nerve disease and axon pathophysiology.</a> International review of neurobiology. 105, 1-17 (2012).</li><li>Fukui, Y., Hayasaka, S., Bedi, K. S., Ozaki, H. S., Takeuchi, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+study+of+the+development+of+the+optic+nerve+in+rats+reared+in+the+dark+during+early+postnatal+life.">Quantitative study of the development of the optic nerve in rats reared in the dark during early postnatal life.</a> Journal of anatomy. 174, 37-47 (1991).</li><li>Celestre, P. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Minimally+invasive+approaches+to+the+cervical+spine.">Minimally invasive approaches to the cervical spine.</a> The Orthopedic clinics of North America. 43 (1), 137-147 (2012).</li><li>Hallas, B. H., Wells, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Novel+Technique+for+Multiple+Injections+into+the+Mammalian+Optic+Nerve.">A Novel Technique for Multiple Injections into the Mammalian Optic Nerve.</a> Kopf Carrier. 54, (2001).</li><li>Harvey, A. R., Hellstrom, M., Rodger, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+therapy+and+transplantation+in+the+retinofugal+pathway.">Gene therapy and transplantation in the retinofugal pathway.</a> Progress in brain research. 175, 151-161 (2009).</li><li>Adachi-Usami, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optic+neuritis--from+diagnosis+to+optic+nerve+transplantation.">Optic neuritis--from diagnosis to optic nerve transplantation.</a> Nippon Ganka Gakkai zasshi. 104 (12), 841-857 (2000).</li><li>Slater, B. J., Vilson, F. L., Guo, Y., Weinreich, D., Hwang, S., Bernstein, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optic+nerve+inflammation+and+demyelination+in+a+rodent+model+of+nonarteritic+anterior+ischemic+optic+neuropathy.">Optic nerve inflammation and demyelination in a rodent model of nonarteritic anterior ischemic optic neuropathy.</a> Investigative ophthalmology &amp; visual science. 54 (13), 7952-7961 (2013).</li><li>Zarbin, M. A., Arlow, T., Ritch, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regenerative+nanomedicine+for+vision+restoration.">Regenerative nanomedicine for vision restoration.</a> Mayo Clinic proceedings. 88 (12), 1480-1490 (2013).</li></ol>

The authors have no meaningful disclosures to report.

Direct injection into the optic nerve of stem cells or other products intended to facilitate regeneration provides a convenient model compared to other means of injections into the CNS. This technique takes less time, requires less total anesthesia, avoids drilling or removing skull or bone tissue, reduces complications rates and allows for more rapid recovery following surgery. 
The most critical steps in this protocol include: 1. Adequate hemostasis in the surgical field to allow clear visua...

视神经为中枢神经系统（CNS）再生的研究，包括眼科疾病如视神经炎，青光眼和创伤的理想地点。的各种干细胞注射要么证明疗效或显示出希望在替换丢失髓磷脂，增加轴突计数和/或预防变性疾病。1,2- 人类视神经含有约120万平行轴突从视网膜到一个直径约为3.0-3.5毫米的视交叉行进。3为了模拟人类疾病在实验室中，老鼠被频繁使用。成年大鼠视神经包含大约100,000轴突直径大约0.5mm范围内。4之一在中枢神经系统的主要限制再生的研究是直接去骨访问。并发症和手术风险的动物都在颅骨或脊椎被删除更高。类似的好处微创方法在脊柱，5个直属视神经注射，无需打开颅骨报价减少并发症和更快的恢复。 该技术已在以前的研究。6在这个手稿和影随行，我们展示了微创方法，以干细胞注入到老鼠视神经。

<table border="0" cellpadding="0" cellspacing="0" width="851">
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		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:151px;">Company</td>
			<td style="width:151px;">Catalog Number</td>
			<td style="width:335px;">Comments/Description</td>
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			<td height="21" style="height:21px;width:216px;">Lewis rat</td>
			<td style="width:151px;">Charles River</td>
			<td align="right" style="width:151px;">4</td>
			<td>Any rat strain will work.</td>
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			<td height="21" style="height:21px;width:216px;">Anesthesia machine</td>
			<td style="width:151px;">Surgivet</td>
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			<td>CDS 9000 Small Animal Anesthesia Machine - Pole Mount</td>
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			<td style="width:151px;">National Optical</td>
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			<td style="width:151px;">Fisher Scientific</td>
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			<td style="width:151px;">Stoelting</td>
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			<td style="width:151px;">Kopf</td>
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			<td height="42" style="height:42px;width:216px;">Pipettes</td>
			<td style="width:151px;">World Precision Instruments</td>
			<td style="width:151px;">18150-6</td>
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			<td style="width:151px;">Harvard Apparatus</td>
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			<td height="42" style="height:42px;width:216px;">Iridectomy scissors</td>
			<td style="width:151px;">Electron Microscopy Sciences</td>
			<td style="width:151px;">Uniband LA-4XF</td>
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</table>

minimally-invasive technique for injection into rat optic nerve

The rat optic nerve is a useful model for stem cell regeneration research. Direct injection into the rat optic nerve allows delivery into the central nervous system in a minimally-invasive surgery without bone removal. This technique describes an approach to visualization and direct injection of the optic nerve following minor fascial dissection from the orbital ridge, using a conjunctival traction suture to gently pull the eye down and out. Representative examples of an injected optic nerve show successful injection of dyed beads.

在实验结束时，处死大鼠，并灌注4％多聚甲醛。视神经被小心解剖和安装成用于低温恒温器切片。 图2示出了在低功率的鼠全视神经其中伊文思蓝染料以可视化的部位注入的一个例子。箭头识别注射的精确位置。此夹层被注射的几分钟内完成由下神经染料的弥散受限所指示的。在其它注射剂，我们观察到对在几个小时的过程中视交叉染料的缓慢扩散。 <p class="jove_content" fo:keep-togethe...

Watch this Scientific Journal Video about Minimally-invasive Technique for Injection into Rat Optic Nerve at JoVE.com

Minimally-invasive Technique for Injection into Rat Optic Nerve

Direct injection into the rat optic nerve is useful for regenerative research. We demonstrate a minimally-invasive technique for direct injection into a rat optic nerve that does not involve opening the skull. Using this method, surgical complications are minimized and recovery is more rapid.

微创技术注入到老鼠视神经

The rat optic nerve is a useful model for stem cell regeneration research. Direct injection into the rat optic nerve allows delivery into the central ...

minimally-invasive-technique-for-injection-into-rat-optic-nerve

Research

JoVE Journal

Neuroscience

9.5K 次观看.  Johns Hopkins University. Direct injection into the rat optic nerve is useful for regenerative research. We demonstrate a minimally-invasive technique for direct injection into a rat optic nerve that does not involve opening the skull. Using this method, surgical complications are minimized and recovery is more rapid. 

视频: Minimally-invasive Technique for Injection into Rat Optic Nerve

Single-unit In vivo Recordings from the Optic Chiasm of Rat

Information about the visual world is transmitted to the brain in sequences of action potentials in retinal ganglion cell axons that make up the optic nerve. In vivo recordings of ganglion cell spike trains in several animal models have revealed much of what is known about how the early visual system processes and encodes visual information. However, such recordings have been rare in one of the most common animal models, the rat, possibly owing to difficulty in detecting spikes fired by small diameter axons. The many retinal disease models involving rats motivate a need for characterizing the functional properties of ganglion cells without disturbing the eye, as with intraocular or in vitro recordings. Here, we demonstrate a method for recording ganglion cell spike trains from the optic chiasm of the anesthetized rat. We first show how to fabricate tungsten-in-glass electrodes that can pick up electrical activity from single ganglion cell axons in rat. The electrodes outperform all commercial ones that we have tried. We then illustrate our custom-designed stereotaxic system for in vivo visual neurophysiology experiments and our procedures for animal preparation and reliable and stable electrode placement in the optic chiasm.

Single-unit In vivo Recordings from the Optic Chiasm of Rat

Retinal ganglion cells transmit visual information from the eye to the brain with sequences of action potentials. Here, we demonstrate how to record the action potentials of single ganglion cells in vivo from anesthetized rats.

单机在体内</em从大鼠视交叉>录音

Information about the visual world is transmitted to the brain in sequences of action potentials in retinal ganglion cell axons that make up the optic ...

科研

神经科学

Axoplasm Isolation from Rat Sciatic Nerve

Isolation of pure axonal cytoplasm (axoplasm) from peripheral nerve is crucial for biochemical studies of many biological processes. In this article, we demonstrate and describe a protocol for axoplasm isolation from adult rat sciatic nerve based on the following steps: (1) dissection of nerve fascicles and separation of connective tissue; (2) incubation of short segments of nerve fascicles in hypotonic medium to release myelin and lyse non-axonal structures; and (3) extraction of the remaining axon-enriched material. Proteomic and biochemical characterization of this preparation has confirmed a high degree of enrichment for axonal components.

We demonstrate a protocol for axoplasm isolation from adult rat sciatic nerve based on dissection of nerve fascicles and incubation in hypotonic medium to release myelin and lyse non-axonal structures, followed by extraction of the remaining axon-enriched material.

从大鼠坐骨神经轴浆隔离

Isolation of pure axonal cytoplasm (axoplasm) from peripheral nerve is crucial for biochemical studies of many biological processes. In this article, we ...

Optic Nerve Transection: A Model of Adult Neuron Apoptosis in the Central Nervous System

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. 
The optic nerve can be accessed within the orbit of the eye and completely transected (axotomized), cutting the axons of the entire RGC population. Optic nerve 
transection is a reproducible model of apoptotic neuronal cell death in the adult CNS 1-4. This model is particularly attractive because the vitreous
 chamber of the eye acts as a capsule for drug delivery to the retina, permitting experimental manipulations via intraocular injections. The diffusion of chemicals 
through the vitreous fluid ensures that they act upon the entire RGC population. Moreover, RGCs can be selectively transfected by applying short interfering RNAs 
(siRNAs), plasmids, or viral vectors to the cut end of the optic nerve 5-7 or injecting vectors into their target, the superior colliculus 8. 
This allows researchers to study apoptotic mechanisms in the desired neuronal population without confounding effects on other bystander neurons or surrounding glia. 
An additional benefit is the ease and accuracy with which cell survival can be quantified after injury. The retina is a flat, layered tissue and RGCs are localized in 
the innermost layer, the ganglion cell layer. The survival of RGCs can be tracked over time by applying a fluorescent tracer (3% Fluorogold) to the cut end of the 
optic nerve at the time of axotomy, or by injecting the tracer into the superior colliculus (RGC target) one week prior to axotomy. The tracer is retrogradely transported, labeling 
the entire RGC population. Because the ganglion cell layer is a monolayer (one cell thick), RGC densities can be quantified in flat-mounted tissue, without the need 
for stereology. Optic nerve transection leads to the apoptotic death of 90% of injured RGCs within 14 days postaxotomy 9-11. RGC apoptosis has a 
characteristic time-course whereby cell death is delayed 3-4 days postaxotomy, after which the cells rapidly degenerate. This provides a time window for 
experimental manipulations directed against pathways involved in apoptosis.

Optic Nerve transection is a widely used model of adult CNS injury. Ninety percent of retinal ganglion cells (RGCs) whose axons are completely transected (axotomy) die within 14 days after axotomy. This model is easily amenable to experimental manipulations and highly reproducible.

视神经横断：一个成人在中枢神经系统的神经元凋亡模型

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. 
The optic nerve can be ...

Methods for Experimental Manipulations after Optic Nerve Transection in the Mammalian CNS

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. The optic nerve can be accessed within the orbit of the eye and completely transected (axotomized), cutting the axons of the entire RGC population. Optic nerve transection is a reproducible model of apoptotic neuronal cell death in the adult CNS 1-4. This model is particularly attractive because the vitreous chamber of the eye acts as a capsule for drug delivery to the retina, permitting experimental manipulations via intraocular injections. The diffusion of chemicals through the vitreous fluid ensures that they act upon the entire RGC population. Viral vectors, plasmids or short interfering RNAs (siRNAs) can also be delivered to the vitreous chamber in order to infect or transfect retinal cells 5-12. The high tropism of Adeno-Associated Virus (AAV) vectors is beneficial to target RGCs, with an infection rate approaching 90% of cells near the injection site 6, 7, 13-15. Moreover, RGCs can be selectively transfected by applying siRNAs, plasmids, or viral vectors to the cut end of the optic nerve 16-19 or injecting vectors into their target the superior colliculus 10. This allows researchers to study apoptotic mechanisms in the injured neuronal population without confounding effects on other bystander neurons or surrounding glia. RGC apoptosis has a characteristic time-course whereby cell death is delayed 3-4 days postaxotomy, after which the cells rapidly degenerate. This provides a window for experimental manipulations directed against pathways involved in apoptosis. Manipulations that directly target RGCs from the transected optic nerve stump are performed at the time of axotomy, immediately after cutting the nerve. In contrast, when substances are delivered via an intraocular route, they can be injected prior to surgery or within the first 3 days after surgery, preceding the initiation of apoptosis in axotomized RGCs. In the present article, we demonstrate several methods for experimental manipulations after optic nerve transection.

Optic Nerve transection is a widely used model of adult CNS injury. This model is ideal for performing a number of experimental manipulations that target the retina globally or directly target the injured neuronal population of retinal ganglion cells.

在哺乳动物的中枢神经系统视神经横断后的实验操作方法

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. The optic nerve can be ...

An Optic Nerve Crush Injury Murine Model to Study Retinal Ganglion Cell Survival

Injury to the optic nerve can lead to axonal degeneration, followed by a gradual death of retinal ganglion cells (RGCs), which results in irreversible vision loss. Examples of such diseases in human include traumatic optic neuropathy and optic nerve degeneration in glaucoma. It is characterized by typical changes in the optic nerve head, progressive optic nerve degeneration, and loss of retinal ganglion cells, if uncontrolled, leading to vision loss and blindness.
The optic nerve crush (ONC) injury mouse model is an important experimental disease model for traumatic optic neuropathy, glaucoma, etc. In this model, the crush injury to the optic nerve leads to gradual retinal ganglion cells apoptosis. This disease model can be used to study the general processes and mechanisms of neuronal death and survival, which is essential for the development of therapeutic measures. In addition, pharmacological and molecular approaches can be used in this model to identify and test potential therapeutic reagents to treat different types of optic neuropathy.
Here, we provide a step by step demonstration of (I) Baseline retrograde labeling of retinal ganglion cells (RGCs) at day 1, (II) Optic nerve crush injury at day 4, (III) Harvest the retinae and analyze RGC survival at day 11, and (IV) Representative result.

This protocol shows how to retrogradely label retinal ganglion cells, and how to subsequently make an optic nerve crush injury in order to analyze retinal ganglion cell survival and apoptosis. It is an experimental disease model for different types of optic neuropathy, including glaucoma.

一个视神经挤压伤的小鼠模型，研究视网膜神经节细胞生存

Injury to the optic nerve can lead to axonal degeneration, followed by a gradual death of retinal ganglion cells (RGCs), which results in irreversible ...

In vivo Imaging of Optic Nerve Fiber Integrity by Contrast-Enhanced MRI in Mice

The rodent visual system encompasses retinal ganglion cells and their axons that form the optic nerve to enter thalamic and midbrain centers, and postsynaptic projections to the visual cortex. Based on its distinct anatomical structure and convenient accessibility, it has become the favored structure for studies on neuronal survival, axonal regeneration, and synaptic plasticity. Recent advancements in MR imaging have enabled the in vivo visualization of the retino-tectal part of this projection using manganese mediated contrast enhancement (MEMRI). Here, we present a MEMRI protocol for illustration of the visual projection in mice, by which resolutions of (200 &#181;m)3 can be achieved using common 3 Tesla scanners. We demonstrate how intravitreal injection of a single dosage of 15 nmol MnCl2 leads to a saturated enhancement of the intact projection within 24 hr. With exception of the retina, changes in signal intensity are independent of coincided visual stimulation or physiological aging. We further apply this technique to longitudinally monitor axonal degeneration in response to acute optic nerve injury, a paradigm by which Mn2+ transport completely arrests at the lesion site. Conversely, active Mn2+ transport is quantitatively proportionate to the viability, number, and electrical activity of axon fibers. For such an analysis, we exemplify Mn2+ transport kinetics along the visual path in a transgenic mouse model (NF-&#954;B p50KO) displaying spontaneous atrophy of sensory, including visual, projections. In these mice, MEMRI indicates reduced but not delayed Mn2+ transport as compared to wild type mice, thus revealing signs of structural and/or functional impairments by NF-&#954;B mutations.
In summary, MEMRI conveniently bridges in vivo assays and post mortem histology for the characterization of nerve fiber integrity and activity. It is highly useful for longitudinal studies on axonal degeneration and regeneration, and investigations of mutant mice for genuine or inducible phenotypes.

In vivo Imaging of Optic Nerve Fiber Integrity by Contrast-Enhanced MRI in Mice

This video illustrates a method, using a clinical 3 T scanner, for contrast-enhanced MR imaging of the na&#239;ve mouse visual projection and for repetitive and longitudinal in vivo studies of optic nerve degeneration associated with acute optic nerve crush injury and chronic optic nerve degeneration in knock-out mice (p50KO).

在视神经纤维通过诚信小鼠对比增强MRI 活体成像

The rodent visual system encompasses retinal ganglion cells and their axons that form the optic nerve to enter thalamic and midbrain centers, and ...

Intramuscular Injections Along the Motor End Plates: A Minimally Invasive Approach to Shuttle Tracers Directly into Motor Neurons

Diseases affecting the integrity of spinal cord motor neurons are amongst the most debilitating neurological conditions. Over the last decades, the development of several animal models of these neuromuscular disorders has provided the scientific community with different therapeutic scenarios aimed at delaying or reversing the progression of these conditions. By taking advantage of the retrograde machinery of neurons, one of these approaches has been to target skeletal muscles in order to shuttle therapeutic genes into corresponding spinal cord motor neurons. Although once promising, the success of such gene delivery approach has been hampered by the sub-optimal number of transduced motor neurons it has so far shown to yield. Motor end plates (MEPs) are highly specialized regions on the skeletal musculature that are in direct synaptic contact to the spinal cord &#945; motor neurons. In this regard, it is important to note that, so far, the efforts to retrogradely transfer genes into motor neurons were made without reference to the location of the MEP region in the targeted muscles. Here, we describe a simple protocol 1) to reveal the exact location of the MEPs on the surface of skeletal muscles and 2) to use this information to guide the intramuscular delivery and subsequent optimal retrograde transport of retrograde tracers into motor neurons. We hope to utilize the results from these tracing experiments in further studies into investigating retrograde transport of therapeutic genes to spinal cord motor neurons through the targeting of MEPs.

The efficacy of intramuscular uptake and retrograde transport of molecules to corresponding motor neurons depends on the location of the injection sites with respect to the motor end plates (MEPs). Here, we describe how to locate MEPs on skeletal muscles to optimise retrograde transport of tracers into motor neurons.

肌肉注射沿运动终板：微创方法来接送示踪剂直接为运动神经元

Diseases affecting the integrity of spinal cord motor neurons are amongst the most debilitating neurological conditions. Over the last decades, the ...

Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination

The visual evoked potential (VEP) recording is widely used in clinical practice to assess the severity of optic neuritis in its acute phase, and to monitor the disease course in the follow-up period. Changes in the VEP parameters closely correlate with pathological damage in the optic nerve. This protocol provides a detailed description about the rodent model of optic nerve microinjection, in which a partial demyelination lesion is produced in the optic nerve. VEP recording techniques are also discussed. Using skull implanted electrodes, we are able to acquire reproducible intra-session and between-session VEP traces. VEPs can be recorded on individual animals over a period of time to assess the functional changes in the optic nerve longitudinally. The optic nerve demyelination model, in conjunction with the VEP recording protocol, provides a tool to investigate the disease processes associated with demyelination and remyelination, and can potentially be employed to evaluate the effects of new remyelinating drugs or neuroprotective therapies.

Focal demyelination is induced in the optic nerve using lysolecithin microinjection. Visual evoked potentials are recorded via skull electrodes implanted over the visual cortex to examine the signal conduction along the visual pathway in vivo. This protocol details the surgical procedures underlying electrode implantation and optic nerve microinjection.

在实验视神经脱髓鞘模型大鼠视觉诱发电位记录

The visual evoked potential (VEP) recording is widely used in clinical practice to assess the severity of optic neuritis in its acute phase, and to ...

Endoscopic Endonasal Trans-sphenoidal Approach: Minimally Invasive Surgery for Pituitary Adenomas

Endoscopic endonasal trans-sphenoidal surgery has become the gold standard for the surgical treatment of pituitary adenomas and many other pituitary lesions. Refinements in surgical techniques, technological advancements, and incorporation of neuronavigation have rendered this surgery minimally invasive. The complication rates of this surgery are very low while excellent results are consistently obtained through this approach.
This paper focuses on the step-by-step surgical approach to pituitary adenomas, which is based on personal experience, and details the results obtained with this minimally invasive surgery.

The aim of this paper is to describe the different steps of the endoscopic endonasal approach to the sella turcica.

内镜下鼻跨蝶入路: 垂体腺瘤的微创手术

Endoscopic endonasal trans-sphenoidal surgery has become the gold standard for the surgical treatment of pituitary adenomas and many other pituitary ...

Minimally Invasive Endoscopic Intracerebral Hemorrhage Evacuation

Intracerebral hemorrhage (ICH) is a subtype of stroke with high mortality and poor functional outcomes, largely because there are no evidence-based treatment options for this devastating disease process. In the past decade, a number of minimally invasive surgeries have emerged to address this issue, one of which is endoscopic evacuation. Stereotactic ICH Underwater Blood Aspiration (SCUBA) is a novel endoscopic evacuation technique performed in a fluid-filled cavity using an aspiration system to provide an additional degree of freedom during the procedure. The SCUBA procedure utilizes a suction device, endoscope, and sheath and is divided into two phases. The first phase involves maximal aspiration and minimal irrigation to decrease clot burden. The second phase involves increasing irrigation for visibility, decreasing aspiration strength for targeted aspiration without disturbing the cavity wall, and cauterizing any bleeding vessels. Using the endoscope and aspiration wand, this technique aims to maximize hematoma evacuation while minimizing collateral damage to the surrounding brain. Advantages of the SCUBA technique include the use of a low-profile endoscopic sheath minimizing brain disruption and improved visualization with a fluid-filled cavity rather than an air-filled one.

This paper details the surgical protocol for minimally invasive endoscopic intracerebral hemorrhage evacuation using the SCUBA technique.

微创内窥镜内腹出血疏散

Intracerebral hemorrhage (ICH) is a subtype of stroke with high mortality and poor functional outcomes, largely because there are no evidence-based ...

Methods Article

微创技术注入到老鼠视神经