Name: visual evoked potential recording in a rat model of experimental optic nerve demyelination
Uploaded: 2015-07-29T14:00:00.000+00:00
Duration: 6 min 49 s
Description: Watch this Scientific Journal Video about Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination at JoVE.com

この研究は、オーストラリアの眼科研究所（ORIA）によってサポートされていました。私たちは当初、VEP記録技術を開発するために私たちを助けるため、教授Algis Vingrys博士バンブイ、メルボルン大学に感謝します。

倫理声明：動物に関わるすべての手順は、ケアと科学的な目的のための動物の使用と眼科と視覚研究における動物の使用に関するARVOステートメントの指針の実践のためのオーストラリアの規範に従って行われ、によって承認されましたマッコーリー大学の動物倫理委員会。 1. VEP電極移植<ol><li>腹腔内ケタミンの注射（75 mgの/ kg）およびメデトミジン（0.5ミリグラム/ kg）で動物を麻酔。 、麻酔の誘導後に手術を開始する指標として離脱反射（ピンチ試験、角膜および眼瞼反射など）と、その不在を守ってください。注意して​​ください。継続的に手術を通して動物を監視し、反射神経が存在する場合、追加の麻酔薬（トップアップあたりの初期ケタミン投与量の10％）を管理。成体ラット（&gt; 12週間）の実験で使用されています。 </li><li>手術領域の皮膚を剃ります。手術中の体温を維持するために加温パッド（37°C）で動物を置きます。ポビドンヨードの局所適用によって皮膚を準備します。手術用ドレープを適用します。全身麻酔下で角膜の乾燥を防ぐために、局所眼軟膏を適用します。滅菌器具を使用して無菌状態を維持します。 </li><li>頭皮の正中線上に縦方向の皮膚切開を行います。頭蓋骨の良い露出を達成するために、結合組織をクリアします。 </li><li>慎重に、ブレグマの後ろに7ミリメートルと正中線に横3ミリメートルでマイクロハンドドリルを使用して手動で小さなバーホールを開けます。 </li><li>約0.5mmの深さに皮質を貫通皮質（領域17）に頭蓋骨を介してインプラントネジ電極。ブレグマに正中線3mmの吻側の基準スクリュー電極を埋め込みます。ネジを包み込むと固定する歯科用セメントを適用します（必ずしも必要ではありません）。 </li><li>頭部の皮膚を縫合、皮膚に抗生物質軟膏を投与し、動物がRECOすることができます温暖化パッドの麻酔からの版。 注：皮膚が各記録に再オープンする必要がないようにあるいは、電極は、露出したままこ​​とができます。手術直後の停止時が、麻酔回復に先立って、非ステロイド性抗炎症薬（NSAID）（術前に投与されていない場合）、またはオピオイド鎮痛薬を投与します。麻酔薬と完全に歩行から完全に回復するまで、常に動物を監視します。 </li><li>動物は前VEP記録に手術から回復するために、少なくとも1週間を許可します。 </li></ol> 2.視神経インジェクション<ol><li> 、動物を麻酔皮膚を準備し、（1.1と1.2）上記のように立体裁断適用されます。 </li><li>ランダムに選択された目の軌道上の皮膚で1〜1.5 cmの切開を行います。微細なアイリスはさみを使用して眼窩に到達するために皮下組織を開きます。結膜を開き、手術用顕微鏡下でテノン嚢を前方。 </li><li>外眼を撤回筋肉やintraobital涙腺は、視神経の約3mmの長さを露出させます。縦方向に眼科ブレードを用いて視神経の周りの硬膜とくも膜物質層を開きます。 </li><li>地球に2mmの後方の距離で視神経にガラスピペットを挿入します。ガラスマイクロピペットは、ハミルトンシリンジに取り付けられています。 </li><li>約30秒の期間にわたって神経にゆっくりと - （髄鞘形成に影響を持っていない0.02％エバンスブルーで、1.0μlの0.4）1％リゾレシチンを注入します。 </li><li>皮膚切開を縫合。感染を防ぐために抗生物質軟膏を適用します。フェロー目は電気生理学の記録のための内部コントロールとして提供することができます。 </li><li>麻酔から回復するために加温パッド上に動物を配置します。 </li></ol> 3. VEPの記録<ol><li>動物を麻酔し、1.1や1.2のように肌を準備します。 注：麻酔薬の低用量は、電気RECOのために使用することができますrding（ケタミン40 mgの/ kg及び0.25ミリグラム/ kgでメデトミジン）。 </li><li>暗い部屋で、ラットを置き、それは5のために闇に適応することができます - 30分。いくつかのケースでは、ラットは、それぞれ明所視VEPの記録8に適合さ暗順応または光に対する暗順応O / Nとすることができます。 </li><li>直腸体温計プローブと恒温ブランケットシステムにより37±0.5℃の体温を維持。 </li><li> 1.0％トロピカミド点眼剤と生徒を拡張。 その場でのスクリュー電極に事前配置にアクセスするために頭蓋骨の上の皮膚を開きます。 </li><li>刺激眼の反対側の視覚皮質とアンプへの基準ネジの上にネジを接続します。グランドとして尾に針電極を挿入します。 5kΩの下の電極インピーダンスを測定し、維持します。 </li><li>優れた目の分離7を提供するために、まぶたの周りの皮膚に直接ミニ全体野の刺激を配置します。刺激装置の照度を予め較正する必要があります光度計による。 </li><li>それぞれ、1〜100ヘルツの低域と高域通過フィルタの設定で、1ヘルツの周波数の光が点滅を通じて100回光刺激を提供します。信号のサンプリングレートは5kHzです。 注：信号は少なくとも約250でサンプリングされるべきである - 3つ以上のサンプルが、各サイクル中に収集されることを保証するために、300ヘルツ。 </li><li>背中の皮膚を縫合し、麻酔から回復するために加温パッド上で動物を飼います。録音を繰り返し、ある期間にわたって機能的変化を監視するために、個々の動物に記録することができます。 </li><li>エンドポイントで、動物を安楽死させるためにナトリウムペントバルビトン（100mg / kg、腹腔内）の過剰投与の注射を投与します。心停止、呼吸停止や体温の低下によって安楽死を確認します。 </li></ol> 4.組織調製および組織学<ol><li>顕微鏡下で安楽死させた動物から視神経を削除し、1％パラホルムアルデヒドO / Nで組織を固定します。 </li> &lt;李&gt;は、生理食塩水で十分に組織を洗ってください。自動組織プロセッサで組織を処置し、パラフィンに埋め込むことができます。回転式ミクロトームを用いて - （10ミクロン5）のセクションをカット。 免疫組織化学研究のために、1％パラホルムアルデヒド中で組織を固定し、生理食塩水で洗浄し、30％スクロース、O / Nでインキュベート：注意してください。 10月に埋め込む組織がメディアを埋め込み、クライオスタットを用いて、凍結切片を作成します。 </li><li> 56℃で、このようなルクソール（95％エタノール）O / Nとして0.1％ファーストブルー溶液中でのセクションをインキュベートします。 30秒間0.05％の炭酸リチウムと他の30秒間、次いで70％エタノールで切片を差別。最後に、切片をマウントする前に30秒間、0.1％クレシルバイオレット溶液で対比染色。視神経5にミエリンを識別するためにファーストブルー染色を使用してください。 </li></ol>

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None of the authors have competing interests or conflicting interests.

The optic nerve is very susceptible to mechanical damage. Optic nerve crush injury over a duration of 1 s can lead to about 75% loss of RGC over a period of 2 weeks10. Therefore, extreme care is required while performing the surgical procedures. According to the authors&#8217; experience, it is much better to adapt a blunt dissection approach to expose and make way through the tissues around the optic nerve along the orientation of the nerve, rather than penetrating in a perpendicular orientation to the optic nerve. Also, the dura and arachnoid mater should be unwraped longitudinally to avoid any axotomy-like damage to the RGC axons. Evan&#8217;s blue is usually used to facilitate the microinjection, as presence of the dye makes the nerve light blue in colour at the injection site.
The reproducibility of VEP recording is critical for this experiment. Different types of anaesthetics and the depth of anaesthesia can affect the VEP waveforms11. We do not recommend using inhaled isoflurane anaesthesia for the VEP study, as isoflurane can lead to burst suppress on the electroencephalogram response12, probably due to GABAergic activity, resulting in more variable VEP traces13. Combination of ketamine/medetomidine anaesthesia provides stable anaesthesia that can quickly be reversed by administration of an alpha receptor antagonist such as atipamazole (2.5 mg/kg i.p). Body temperature can also have a significant impact on the speed of nerve conduction, especially in demyelinated nerves. Temperature-dependant changes in visual evoked potentials have been observed in rat VEPs and latencies were observed to be significantly longer as body temperature was lowered14,15. Hence, it is important to maintain a uniform body temperature using a homoeothermic blanket system during the VEP recordings.
Also, it is important to understand that the pathogenesis of lysolecithin-induced demyelination differs from that in optic neuritis or multiple sclerosis. Lysolecithin-induced demyelination results from the detergent like action of the toxin upon myelin lipids rather than immune-mediated inflammatory reaction, which is usually seen in the real disease scenarios16. If the study aims to investigate the mechanisms of demyelination/axonal damage in multiple sclerosis, an immune-mediated demyelination model, such as experimental autoimmune encephalomyelitis (EAE)17, should be considered. The advantage of using the toxin-induced demyelination model is that a focal lesion in the optic nerve can be produced and monitored longitudinally. In contrast to the brain lesions, the effects of demyelinated lesions on the optic nerve are more clinically apparent and measureable (lesion size can be accurately determined by VEPs or MRI imaging). Although remyelination in the optic nerve appeared to be not as pronounced as that observed previously in the case of spinal cord18, this optic nerve injection model, in conjunction with the VEP recording technique, is able to provide a superior tool to monitor the process of demyelination and remyelination in vivo, and to potentially evaluate new remyelinating therapies.

Optic neuritis is one of the most common form of optic neuropathy, causing complete or partial loss of vision1. Histologically, it is featured by inflammatory demyelination, retinal ganglion cell axonal loss and varying degrees of remyelination in the optic nerve2. Optic neuritis is usually the manifest onset of multiple sclerosis. The visual evoked potential (VEP) is a non-invasive tool for investigating the function of the visual system. It reflects the post-retinal function from the retina to the primary visual cortex and is affected in many optic nerve disease conditions3. The VEP has been predominantly used in optic neuritis patients to assess the integrity of the visual pathway4. 
The latency of VEP, which reflects the velocity of signal conduction along the visual pathway, is considered to be an accurate measurement of the level of myelin associated changes in the optic nerve5; while the amplitude of VEP is believed to be closely correlated with axonal damage of the retinal ganglion cells (RGC)6. This hypothesis has been fairly well established using the rat model of lysolecithin-induced optic nerve demyelination5. 
Here, we explicate a comprehensive protocol of optic nerve microinjection technique in rodents, which can minimise the surgical manipulation-related damage to the nerve per se as well as to the adjacent tissues such as extraocular muscles and blood vessels. Also, the skull electrode implantation surgery has been described for VEP recording in animals7. The VEP recordings can be repeatedly carried out on animals over a period of time to assess demyelination/remyelination related changes as well as impact on axonal integrity in the optic nerve.

<table><tbody><tr><td>Ketamine 100 mg/ml (Ketamil)</td><td>Troy Laboratories</td><td>AC 116</td><td></td></tr><tr><td>Medetomidine 1 mg/ml (Domitor)</td><td>Pfizer</td><td>sc-204073</td><td></td></tr><tr><td>Tropicamide 1.0% (Mydriacyl)</td><td>Alcon</td><td>sc-202371</td><td></td></tr><tr><td>Homoeothermic blanket system</td><td>Harvard Apparatus</td><td>NC9203819</td><td></td></tr><tr><td>Impedance meter&amp;nbsp;</td><td>Grass</td><td>F-EZM5</td><td></td></tr><tr><td>Screw electrodes&amp;nbsp;</td><td>Micro Fasteners</td><td>M1.0&amp;times;3mm Csk Slot M/T 304 S/S</td><td></td></tr><tr><td>Subdermal needle electrodes&amp;nbsp;</td><td>Grass</td><td>F-E3M-72</td><td></td></tr><tr><td>Rapid Repair&amp;nbsp;</td><td>DeguDent GmbH</td><td></td><td></td></tr><tr><td>Light-emitting diode&amp;nbsp;</td><td>Nichia</td><td>NSPG300A</td><td></td></tr><tr><td>Bioamplifier</td><td>CWE, Inc.</td><td>BMA-400</td><td></td></tr><tr><td>CED system</td><td>Cambridge Electronic Design, Ltd.</td><td>Power1401</td><td></td></tr><tr><td>Hamilton syringe&amp;nbsp;</td><td>Hamilton</td><td>87930</td><td></td></tr><tr><td>Lysolecithin</td><td>Sigma</td><td>L4129</td><td></td></tr><tr><td>Evan&amp;rsquo;s blue&amp;nbsp;</td><td>Sigma</td><td>E2129</td><td></td></tr></tbody></table>

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.

再現内会合VEPトレースは、 図1に示されており、N1潜時の有意な遅延は、視神経の注射後に見られます。脱髄の部分視神経病変は、ルクソールファーストブルー染色5を用いて、組織切片上で観察することができる。 図2は、視神経の中心部にある小さな焦点脱髄病変を持つ代表的な断面を示しています。断面は、病変の総体積を表すものではありませんので注意してください。脱髄の領域は、三次元再構成を用いて病変容積を推定するために、神経の各連続した断面で測定することができます。我々は、我々の以前の研究で、このモデルを使用して、待ち時間遅延および損傷体積の間に強い相関関係を示したし、生理食塩水を注射した対照5にはVEPの待ち時間遅延はありませんでした。 これは、フラッシュ照明後の初期VEP成分がより安定であると考えられている7 </sup&gt;と主レチノ - 膝状繊維を介して一次視覚野の励起によって影響を受けます。我々の研究は、N1遅延が視神経5における脱髄との最強の線形関係を有することが示されています。したがって、我々は、N1の待ち時間は、データ分析のためおよび療法を再ミエリン化の影響を評価する際に縦VEPモニタリングに使用することをお勧めします。 VEPの振幅は、待ち時間に比べ変数が、視神経6における軸索の機能をさらに示します。脳波ベースのスケーリングは、振幅分析の9を検討することができます。 <img alt="図1" src="/files/ftp_upload/52934/52934fig1.jpg" /> 視神経注入後の図1 VEP遅延。代表VEPは、個々の前に、ラットおよび視神経マイクロインジェクション（0.8μlのリゾレシチン）2日後からトレースします。 VEPの記録は、各日に繰り返した（イントラ会期トレースはショーですこのVEP記録プロトコルの再現性を実証するために、同じ色のN）。 （垂直スケールバー：10μV、水平スケールバー：10ミリ秒）。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/52934/52934fig1large.jpg" target="_blank">この図の拡大版を表示するには、こちらをクリックしてください。</a> <img alt="図2." src="/files/ftp_upload/52934/52934fig2.jpg" /> 視神経図2.脱髄。マイクロインジェクションをリゾレシチン後のラットから視神経の代表断面。ミエリン成分は、ルクソールファーストブルーを用いて青色に染色されます。脱髄の小さな焦点病変部の中心に見ることができます。脱髄面積は3次元スケールで病変体積を推定するために、長手方向連続断面上で測定することができる。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/52934/52934fig2large.jpg" target="_blank">この図の拡大版を表示するには、こちらをクリックしてください。</a>

Watch this Scientific Journal Video about Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination at JoVE.com

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

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.

実験視神経の脱髄のラットモデルにおける視覚誘発電位の記録

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 ...

visual-evoked-potential-recording-rat-model-experimental-optic-nerve

Universidad San Sebastian

Research

JoVE Journal

Neuroscience

12.2K ビュー.  Macquarie University. 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. 

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

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.

シングルユニット in vivoで</emラットの視交叉から>録音

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 ...

神経科学

Implantation and Recording of Wireless Electroretinogram and Visual Evoked Potential in Conscious Rats

The full-field electroretinogram (ERG) and visual evoked potential (VEP) are useful tools to assess retinal and visual pathway integrity in both laboratory and clinical settings. Currently, preclinical ERG and VEP measurements are performed with anesthesia to ensure stable electrode placements. However, the very presence of anesthesia has been shown to contaminate normal physiological responses. To overcome these anesthesia confounds, we develop a novel platform to assay ERG and VEP in conscious rats. Electrodes are surgically implanted sub-conjunctivally on the eye to assay the ERG and epidurally over the visual cortex to measure the VEP. A range of amplitude and sensitivity/timing parameters are assayed for both the ERG and VEP at increasing luminous energies. The ERG and VEP signals are shown to be stable and repeatable for at least 4 weeks post surgical implantation. This ability to record ERG and VEP signals without anesthesia confounds in the preclinical setting should provide superior translation to clinical data.

We show surgical implantation and Recording procedures to measure visual electrophysiological signals from the eye (electroretinogram) and brain (visual evoked potential) in conscious rats, which is more analogous to the human condition where recordings are conducted without anesthesia confounds.

覚醒ラットに移植し、無線電図の記録と視覚誘発電位

The full-field electroretinogram (ERG) and visual evoked potential (VEP) are useful tools to assess retinal and visual pathway integrity in both ...

行動学

Rat Model of Photochemically-Induced Posterior Ischemic Optic Neuropathy

Posterior Ischemic optic neuropathy (PION) is a sight-devastating disease in clinical practice. However, its pathogenesis and natural history have&#160;remained poorly understood. Recently, we developed a reliable, reproducible animal model of PION and tested the treatment effect of some neurotrophic factors in this model1. The purpose of this video is to demonstrate our photochemically induced model of posterior ischemic optic neuropathy, and to evaluate its effects with retrograde labeling of retinal ganglion cells. Following surgical exposure of the posterior optic nerve, a photosensitizing dye, erythrosin B, is intravenously injected and a laser beam is focused onto the optic nerve surface. Photochemical interaction of erythrosin B and the laser during irradiation damages the vascular endothelium, prompting microvascular occlusion mediated by platelet thrombosis and edematous compression. The resulting ischemic injury yields a gradual but pronounced retinal ganglion cell dieback, owing to a loss of axonal input - a remote, injury-induced and clinically relevant outcome. Thus, this model provides a novel platform to study the pathophysiologic course of PION,&#160;and can be further optimized for testing therapeutic approaches for optic neuropathies as well as other CNS ischemic diseases.

The goal of this protocol is to photochemically induce ischemic injury to the posterior optic nerve in rat. This model is critical to studies of the pathophysiology of posterior ischemic optic neuropathy, and therapeutic approaches for this and other optic neuropathies, as well as of other CNS ischemic diseases.

光化学誘起後方虚血性視神経障害のラットモデル

Posterior Ischemic optic neuropathy (PION) is a sight-devastating disease in clinical practice. However, its pathogenesis and natural history ...

医学

Simultaneous Recording of Electroretinography and Visual Evoked Potentials in Anesthetized Rats

The electroretinogram (ERG) and visual evoked potential (VEP) are commonly used to assess the integrity of the visual pathway. The ERG measures the electrical responses of the retina to light stimulation, while the VEP measures the corresponding functional integrity of the visual pathways from the retina to the primary visual cortex following the same light event. The ERG waveform can be broken down into components that reflect responses from different retinal neuronal and glial cell classes. The early components of the VEP waveform represent the integrity of the optic nerve and higher cortical centers. These recordings can be conducted in isolation or together, depending on the application. The methodology described in this paper allows simultaneous assessment of retinal and cortical visual evoked electrophysiology from both eyes and both hemispheres. This is a useful way to more comprehensively assess retinal function and the upstream effects that changes in retinal function can have on visual evoked cortical function.

This protocol describes simultaneous measurement of electroretinogram and visual evoked potentials in anesthetized rats.

麻酔ラットにおける電図および視覚誘発電位の同時記録

The electroretinogram (ERG) and visual evoked potential (VEP) are commonly used to assess the integrity of the visual pathway. The ERG measures the ...

Visual Evoked Potential Recordings in Mice Using a Dry Non-invasive Multi-channel Scalp EEG Sensor

For scalp EEG research environments with laboratory mice, we designed a dry-type 16 channel EEG sensor which is non-invasive, deformable, and re-usable because of the plunger-spring-barrel structural facet and mechanical strengths resulting from metal materials. The whole process for acquiring the VEP responses in vivo from a mouse consists of four steps: (1) sensor assembly, (2) animal preparation, (3) VEP measurement, and (4) signal processing. This paper presents representative measurements of VEP responses from multiple mice with a submicro-voltage signal resolution and sub-hundred millisecond temporal resolution. Although the proposed method is safer and more convenient compared to other previously reported animal EEG acquiring methods, there are remaining issues including how to enhance the signal-to-noise ratio and how to apply this technique with freely moving animals. The proposed method utilizes easily available resources and shows a repetitive VEP response with a satisfactory signal quality. Therefore, this method could be utilized for longitudinal experimental studies and reliable translational research exploiting non-invasive paradigms.

We designed a dry-type 16 channel EEG sensor which is non-invasive, deformable, and re-usable. This paper describes the whole process from manufacturing the proposed EEG electrode to signal processing of visual evoked potential (VEP) signals measured on a mouse scalp using a dry non-invasive multi-channel EEG sensor.

誘発電位録画ドライの非侵襲的なマルチ チャネルを使用してマウスの頭皮脳波センサー

For scalp EEG research environments with laboratory mice, we designed a dry-type 16 channel EEG sensor which is non-invasive, deformable, and re-usable ...

In Vivo Methods to Assess Retinal Ganglion Cell and Optic Nerve Function and Structure in Large Animals

The optic nerve collects axons signals from the retinal ganglion cells and transmits visual signal to the brain. Large animal models of optic nerve injury are essential for translating novel therapeutic strategies from rodent models to clinical application due to their closer similarities to humans in size and anatomy. Here we describe some in vivo methods to evaluate the function and structure of the retinal ganglion cells (RGCs) and optic nerve (ON) in large animals, including visual evoked potential (VEP), pattern electroretinogram (PERG) and optical coherence tomography (OCT). Both goat and non-human primate were employed in this study. By presenting these in vivo methods step by step, we hope to increase experimental reproducibility among different labs and facilitate the usage of large animal models of optic neuropathies.

In Vivo Methods to Assess Retinal Ganglion Cell and Optic Nerve Function and Structure in Large Animals

Here we demostrate several in vivo tests (flash visual evoked potential, pattern electroretinogram and optic coherence tomography) in goat and rhesus macaque to understand the structure and function of the optic nerve and its neurons.

イン・ヴィヴォ 大型動物の眼球神経節細胞と視神経機能と構造を評価する方法

The optic nerve collects axons signals from the retinal ganglion cells and transmits visual signal to the brain. Large animal models of optic nerve injury ...

Inducing Local Demyelination in the Optic Nerve Using Lysolecithin

Source: You, Y. et al., <a href="https://app-jove-com.bdigitaluss.remotexs.co/v/52934">Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination.</a> J. Vis. Exp. (2015)
This video demonstrates the procedure of surgically accessing the optic nerve in an anesthetized animal and precisely delivering lysolecithin to induce focal demyelination, creating neuropathological conditions for further study.

リゾレシチンを用いた視神経の局所脱髄誘導

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board. ...

JoVE Encyclopedia of Experiments

Neuropathology

Epilepsy and Seizure Disorders

Preparing a Rat Model to Assess Visual Pathway Integrity Using an Electrophysiology Setup

Source: Nguyen, C. T. et al., <a href="https://app-jove-com.bdigitaluss.remotexs.co/v/54158">Simultaneous Recording of Electroretinography and Visual Evoked Potentials in Anesthetized Rats.</a>&#160;J. Vis. Exp. (2016)
This video demonstrates the preparation of a rat model to study retinal health and visual pathway integrity. Visual evoked potential and electroretinography reference and active electrodes are connected to the rat, followed by aligning the platform with the rat in front of the Ganzfeld bowl for even retinal illumination and closing the Faraday cage to avoid external interference.

電気生理学セットアップを使用して視覚経路の完全性を評価するためのラットモデルの準備

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. ...

Neurophysiology

Electrophysiology Techniques

Electron Microscopic Analysis of Myelin Damage in a Rat Model of Optic Nerve Injury

Take fixed optic nerve sections from a control rat and a rat with optic nerve injury.
The control section exhibits axons with tightly packed myelin sheaths containing concentric plasma membrane layers. The injured section exhibits decompacted myelin with large gaps.
Incubate with an osmium-ferrocyanide complex that binds to lipids and enhances the myelin sheath&#39;s contrast.
Treat with thiocarbohydrazide to create additional binding sites for osmium.
Reapply osmium to further enhance lipid contrast.
Stain with heavy metals, which bind to macromolecules and enhance structural contrast.
Dehydrate using increasing alcohol concentrations and rinse with acetone for resin embedding.
Embed the tissue in resin, and coat the resin with gold to improve image quality.
Use serial block-face scanning electron microscopy to simultaneously slice and image. Focus the electron beam on the surface and detect the backscattered electrons to generate images.
Myelin sheaths appear dark, while spaces within damaged sheaths appear lighter, allowing differentiation between normal and damaged myelin.

視神経損傷ラットモデルにおけるミエリン損傷の電子顕微鏡的解析

Neuromuscular Disorders

Recording of Visual Evoked Potentials via the Skull Electrodes in a Rat Model

Source: You, Y., et al. <a href="https://app-jove-com.bdigitaluss.remotexs.co/v/52934">Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination.</a> J. Vis. Exp. (2015).
This video demonstrates the process of measuring visual evoked potentials or VEPs in a dark-adapted, anesthetized rat with pre-implanted skull electrodes, which record the electrical signals from the brain&#39;s visual cortex in response to light stimuli.

ラットモデルにおける頭蓋骨電極による視覚誘発電位の記録

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. VEP ...

実験視神経の脱髄のラットモデルにおける視覚誘発電位の記録

要約

さらに動画を探す

この動画の章

シングルユニット in vivoで録音

覚醒ラットに移植し、無線電図の記録と視覚誘発電位

光化学誘起後方虚血性視神経障害のラットモデル

麻酔ラットにおける電図および視覚誘発電位の同時記録

誘発電位録画ドライの非侵襲的なマルチチャネルを使用してマウスの頭皮脳波センサー

イン・ヴィヴォ大型動物の眼球神経節細胞と視神経機能と構造を評価する方法

リゾレシチンを用いた視神経の局所脱髄誘導

電気生理学セットアップを使用して視覚経路の完全性を評価するためのラットモデルの準備

視神経損傷ラットモデルにおけるミエリン損傷の電子顕微鏡的解析

ラットモデルにおける頭蓋骨電極による視覚誘発電位の記録

実験視神経の脱髄のラットモデルにおける視覚誘発電位の記録

要約

さらに動画を探す

この動画の章

シングルユニット in vivoで録音

覚醒ラットに移植し、無線電図の記録と視覚誘発電位

光化学誘起後方虚血性視神経障害のラットモデル

麻酔ラットにおける電図および視覚誘発電位の同時記録

誘発電位録画ドライの非侵襲的なマルチ チャネルを使用してマウスの頭皮脳波センサー

イン・ヴィヴォ 大型動物の眼球神経節細胞と視神経機能と構造を評価する方法

リゾレシチンを用いた視神経の局所脱髄誘導

電気生理学セットアップを使用して視覚経路の完全性を評価するためのラットモデルの準備

視神経損傷ラットモデルにおけるミエリン損傷の電子顕微鏡的解析

ラットモデルにおける頭蓋骨電極による視覚誘発電位の記録

誘発電位録画ドライの非侵襲的なマルチチャネルを使用してマウスの頭皮脳波センサー

イン・ヴィヴォ大型動物の眼球神経節細胞と視神経機能と構造を評価する方法