Wir danken den vielen Studenten und Stipendiaten, die auf diesem Modell gearbeitet haben, um ihre Wirksamkeit zu verbessern und ihre Mechanismen zu verstehen. Ein besonderer Dank an Dr. gebührt. Mary Johnson (University of Maryland-Baltimore), Nitza Goldenberg-Cohen (Schneiderman Childrens Hospital, Petah-Tikva, Israel), Charles Zhang (Einstein Medical College, Bronx, NY) und Valerie Touitou (Hopital Salpetrie, Paris, Frankreich). Diese Studie wurde teilweise durch RO1 EY015304 zu SLB finanziert.

(; Baltimore, MD, USA IACUC) Dieses Protokoll wurde von der University of Maryland Institutional Animal Care and Utilization Ausschuss genehmigt 1. Experimenteller Aufbau <ol><li> Machen Sie eine kundenspezifische Kontaktlinse aus einem klaren optischer Qualität Kreis 7 mm Durchmesser Plexiglas, 3 mm Dicke. Schneiden Sie die Rundlinsen mit einer Bohrmaschine. Verwenden Sie ein Standard-Bohrer, um die innere Kurve machen und polieren schließlich die äußeren und inneren Kurven eine Kontaktlinse Polierer ultrafeiner Körnung mit (1000/3000). </li><li> Bereiten 2,5 mM Bengalrosa (RB) in pH 7,4 Phosphatpuffer-Salzlösung (PBS) im Voraus, Sterilisieren Filter mit einem 0,45-Mikron-Spritzenfilter und Speicher 1 ml Aliquots in 20 ° C in einem lichtdichten Behälter für bis zu 6 Monate. HINWEIS: Die Verwendung von Albino outbred männlichen Tieren, wie Sprague Dawley minimiert die Belastung abhängige Antwort Unterschiede ermöglicht leichtere Induktions und reduziert die Variabilität, die mit der Brunst cycli auftreten kannng weiblich. </li><li> Richten Sie verdoppelt die Frequenz Neodym-Yttrium-Aluminium-Granat (Fd-YAG) ophthalmische medizinische Laser, der eine 532 nm Laserlicht erzeugt. Montieren Sie den Laser auf einem Haag-Streit ophthalmologischen Spaltlampe ein Standard-ophthalmologischen Laser-Adapter. Das im Handel erhältliche Gerät ermöglicht die gleichzeitige Visualisierung des Auges und der Laserpunkt Anwendung des Tieres. Der medizinische Laser hat auch einen Zielstrahl für die richtige Fokussierung und Zentrierung mit gleichen Punktgröße wie Laserinduktion. Laser Leistungsparameter sind wie folgt: <ol><li> Für Ratte rNAION Induktion: Verwenden Sie 500 um Spotgröße / 50 mW Laserleistung / 1.000 ms Dauer / 1.000 ms Intervall. </li><li> Für Maus rNAION Induktion: die Punktgröße auf 300 &amp; mgr; m für kleinere Papille ändern und andere Parameter, die die gleiche wie die Ratte Einstellung verlassen. </li><li> Verwenden Sie regelmäßig ein Laserleistungsmesser der Laserleistung zu gewährleisten. </li></ol></li></ol> 2. Experimentelles Verfahren <ol><li> Schalten Sie die Laserleistungund stellen Sie den entsprechenden Laserparameter auf. Erwärmen Sie den Laser für mindestens fünf Minuten vor dem Gebrauch. </li><li> Wiegen Sie das Tier die geeignete Dosis für Ketamin / Xylazin und RB Farbstoff zu bestimmen. Anästhesieren das Tier durch intraperitoneale Injektion einer 1 ml / kg Gemisch von 80 mg / ml Ketamin und 4 mg / ml Xylazin. </li><li> Lassen Sie das Tier in einem beheizten Käfig, bis sie vollständig betäubt. Prüfen Sie, ob keine Antwort auf aversiven Reizen (Schwanz oder Zeh Prise). Überprüfen Sie Tiere für Narkosetiefe alle 10 min. </li><li> Erweitern die Schüler des Tieres mit 1% Tropicamid und betäuben die Oberfläche des Auges mit 0,5% Proparacain. Bei der Verwendung von pigmentierten Tieren, wie Long Evans, ein 2,5% Neosynephrin Augentropfen wird Pupillenerweiterung erhöhen. </li><li> Mit einer Schere die Whiskers nahe der Mündung auf der Seite zu schneiden, um die Ansicht zu vermeiden induziert werden blockiert. </li><li> Geben Sie einen Tropfen von 1% Methylcellulose oder andere ophthalmische Kupplungsabfall an der Innenseite des maßgeschneiderte Kontaktlinse, und wenden Sie dann das Objektiv auf ter Ratte Auge. </li><li> Legen Sie das Tier auf einer Plattform auf die Höhe der Spaltlampe eingestellt. Gesetzt den Kopf des Tieres in einem 45 ° Winkel, so dass sich das Auge an der Spaltlampe und Laserstrahls senkrecht ist. </li><li> Visualisieren Sie das Auge durch die Augenspaltlampe. Stellen Sie sicher, dass der Zielstrahl ist die richtige Größe sowie fokussiert und zentriert direkt auf der visualisierten Sehnerv. Fotografieren Sie das Netzhautfundus eine Digitalkamera mit hoher ASA mit (1200 - 2000) auf einem der Okulare der Spaltlampe mit einem Maß Adapter montiert Geschwindigkeit. HINWEIS: Die Fähigkeit, die Choroidealgefässe zeigt die Transparenz der Netzhaut zu sehen. Dies ist ein wichtiges Zeichen, um später retinaler Ischämie zu erkennen zu können, was die Interpretation verwechseln kann, wenn sie auftritt. rNAION ist Sehnerv Ischämie, die in isolierten RGC Verlust führt, während retinaler Ischämie führt zu Schädigungen der Netzhaut alle Zellen der inneren Netzhautschichten zu beeinflussen. </li><li> Optional können weitere Bild der Netzhaut undSehnerv einen Spektralbereich-optischen Kohärenztomographen (SD-OCT 8) unter Verwendung der nichtinduzierten Auge zu evaluieren. Scannen en face (3B) sowie 7 Querschnitts Scans durch die Retina (3C). Die SD-OCT-Bildgebung verwendet die gleiche Kontaktlinse für die Laser-Induktion eingesetzt. </li><li> Injizieren von 1 ml / kg RB intravenös durch die Schwanzvene, und warten Sie für 30 Sekunden, dann aktivieren Sie die Laserleistung. Diese Zeitverzögerung ermöglicht die RB gleichmäßig in der Zirkulation zu verteilen. Wir verwenden einen 50 mW Laserpuls an einem s / Puls. Größere Energien (≥ 60 mW) können die Netzhaut schädigen oder retinale vaskuläre Ischämie verursachen. Achtung: Stellen Sie sicher , dass jeder hat ein Paar von Laserschutzfiltergläser der entsprechenden Sperr Wellenlänge Streu Eingabe Laserlicht Ermittler Auge zu verhindern. HINWEIS: Die Laser Verabreichung rasch nach der IV RB Injektion verabreicht werden muss, da der Farbstoff schnell aus dem Kreislauf eliminiert wird. Je länger die Laserinduzierung, desto schwerer der Sehnerv Ischämie. 12 sec Impulse in schneller Abfolge - In der Regel werden die Tiere 7 angegeben. Der Kontakt des Laserlichts mit dem zirkulierenden Farbstoff gibt den Sehnerv Gefäße einen schönen goldenen Glanz, der durch die Spaltlampe (4B) zu sehen ist. Dies erweist sich der Farbstoff systemisch injiziert und in den Blutstrom verteilt. Wenn die Glut schwach ist, oder gar keine (4A) wurde der Farbstoff nicht intravenös injiziert. In diesem Fall wird keine zweite Injektion sofort geben, da das Tier für mindestens zwei Tage vor Reinjektion erholen müssen. </li><li> Unmittelbar nach der Induktion, entfernen Sie die Kontaktlinse. Decken Sie beide Augen mit Augen Triple-Antibiotikum (Neosporin / Polymyxin / Bacitracin) Salbe mit Dexamethason, und legen Sie das Tier auf einem 37 ° C Erwärmung Pad in einem einzigen untergebracht Käfig unter strenger Beobachtung bis zur vollständigen Genesung. <ol><li> Reinigen Sie die Kontaktlinse mit destilliertem water und für die zukünftige Verwendung mit einem nicht scheuernden Reinigungstuch trocken wischen. </li><li> Zwei Tage nach der Induktion bewerten den Sehnerv Ödem sowohl Fundus Farbfotografie und SD-OCT - Analyse 8. HINWEIS: Um den Grad der Sehnerv Ödem gibt Ischämie eine Abschätzung der Schwere des Sehnervs Vergleich. An zwei Tagen wird der Sehnerv Scheibe Rand unscharf, und die Netzhautvenen leicht erweitert werden, im Vergleich mit der Gegenseite (un-induzierten) Auge. Führen Sie Elektroretinogramm (ERG) und Flash - visuell evozierten Potential (VEP 11) auf zwei und vier Wochen nach der Induktion für die Elektroanalyse. </li></ol></li></ol>

<ol>
	<li>Banik, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nonarteritic+Anterior+Ischemic+Optic+Neuropathy:+An+Update+on+Demographics,+Clinical+Presentation,+Pathophysiology,+Animal+Models,+Prognosis,+and+Treatment.">Nonarteritic Anterior Ischemic Optic Neuropathy: An Update on Demographics, Clinical Presentation, Pathophysiology, Animal Models, Prognosis, and Treatment.</a> J. Clin. Experimental Ophthalmol. 10, 1-5 (2013).</li><li>IONDT study group. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characteristics+of+patients+with+nonarteritic+anterior+ischemic+optic+neuropathy+eligible+for+the+Ischemic+Optic+Neuropathy+Decompression+Trial.">Characteristics of patients with nonarteritic anterior ischemic optic neuropathy eligible for the Ischemic Optic Neuropathy Decompression Trial.</a> Arch Ophthalmol. 114, 1366-1374 (1996).</li><li>Tesser, R. A., Niendorf, E. R., 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=The+morphology+of+an+infarct+in+nonarteritic+anterior+ischemic+optic+neuropathy.">The morphology of an infarct in nonarteritic anterior ischemic optic neuropathy.</a> Ophthalmology. 110, 2031-2035 (2003).</li><li>Bernstein, S. L., Johnson, M. A., Miller, N. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nonarteritic+anterior+ischemic+optic+neuropathy+(NAION)+and+its+experimental+models.">Nonarteritic anterior ischemic optic neuropathy (NAION) and its experimental models.</a> Prog Retin Eye Res. 30, 167-187 (2011).</li><li>Nicholson, J. D., 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=PGJ2+Provides+Prolonged+CNS+Stroke+Protection+by+Reducing+White+Matter+Edema.">PGJ2 Provides Prolonged CNS Stroke Protection by Reducing White Matter Edema.</a> PLoS One. 7 (12), (2012).</li><li>Goldenberg-Cohen, N., 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=Oligodendrocyte+Dysfunction+Following+Induction+of+Experimental+Anterior+Optic+Nerve+Ischemia.">Oligodendrocyte Dysfunction Following Induction of Experimental Anterior Optic Nerve Ischemia.</a> Invest Ophthalmol Vis Sci. 46, 2716-2725 (2005).</li><li>Bernstein, S. L., Guo, Y., Kelman, S. E., Flower, R. W., Johnson, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+and+cellular+responses+in+a+novel+rodent+model+of+anterior+ischemic+optic+neuropathy.">Functional and cellular responses in a novel rodent model of anterior ischemic optic neuropathy.</a> Invest Ophthalmol Vis Sci. 44, 4153-4162 (2003).</li><li>Berger, A., 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=Spectral-Domain+Optical+Coherence+Tomography+of+the+Rodent+Eye:+Highlighting+Layers+of+the+Outer+Retina+Using+Signal+Averaging+and+Comparison+with+Histology.">Spectral-Domain Optical Coherence Tomography of the Rodent Eye: Highlighting Layers of the Outer Retina Using Signal Averaging and Comparison with Histology.</a> PLoS One. 9 (5), (2014).</li><li>Huang, T. L., 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=Protective+effects+of+systemic+treatment+with+methylprednisolone+in+a+rodent+model+of+non-arteritic+anterior+ischemic+optic+neuropathy+(rNAION).">Protective effects of systemic treatment with methylprednisolone in a rodent model of non-arteritic anterior ischemic optic neuropathy (rNAION).</a> Exp Eye Res. 131, 69-76 (2015).</li><li>Mantopoulos, D., 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=An+Experimental+Model+of+Optic+Nerve+Head+Injury.">An Experimental Model of Optic Nerve Head Injury.</a> Invest Ophthalmol Vis Sci. 57, 6222 (2014).</li><li>You, Y., 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=Visual+Evoked+Potential+Recording+in+a+Rat+Model+of+Experimental+Optic+Nerve+Demyelination.">Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination.</a> J. Vis. Exp. (101), e52934 (2015).</li><li>Templeton, J. P., Geisert, E. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+practical+approach+to+optic+nerve+crush+in+the+mouse.">A practical approach to optic nerve crush in the mouse.</a> Mol Vis. 18, 2147-2152 (2012).</li><li>Magharious, M. M., D'Onofrio, P. M., Koeberle, P. D. <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+Transection:+A+Model+of+Adult+Neuron+Apoptosis+in+the+Central+Nervous+System.">Optic Nerve Transection: A Model of Adult Neuron Apoptosis in the Central Nervous System.</a> J Vis Exp. (51), e2241 (2011).</li><li>Wang, Y., 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=A+Novel+Rodent+Model+of+Posterior+Ischemic+Optic+Neuropathy.">A Novel Rodent Model of Posterior Ischemic Optic Neuropathy.</a> JAMA Ophthalmol. 131 (2), 194-204 (2013).</li><li>Huang, T. L., Chang, C. H., Chang, S. W., Lin, K. H., Tsai, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficacy+of+Intravitreal+Injections+of+Antivascular+Endothelial+Growth+Factor+Agents+in+a+Rat+Model+of+Anterior+Ischemic+Optic+Neuropathy.">Efficacy of Intravitreal Injections of Antivascular Endothelial Growth Factor Agents in a Rat Model of Anterior Ischemic Optic Neuropathy.</a> IOVS. 56, 2290-2296 (2015).</li></ol>

Autoren haben nichts zu offenbaren.

Zwar gibt es eine Reihe von Modellen der Schädigung des Sehnervs (Sehnerv Crush 12, Sehnervdurchtrennung 13 und PION 14) sind, ist das rNAION Modell humane, anpassungsfähig sowohl an Ratten und Mäusen. Es ähnelt mehr dem menschlichen klinischen Zustand von NAION. Dieser Zustand beinhaltet progressive anterioren Sehnerv Ödem, eine vordere Sehnerv Kompartmentsyndrom, fokale axonalen Ischämie, isoliert retinaler Ganglionzellen axonalen Schäden und Verluste über einen längeren Zeitv...

Nonarteritic anteriore ischämische Optikusneuropathie (NAION) ist eine fokale ischämische Läsion des vorderen Teils des Sehnervs (ON) 1. NAION ist die häufigste Ursache für den plötzlichen Sehnerv im Zusammenhang mit Sehverlust bei Personen im Alter von 50 2. Der Mechanismus wird angenommen , dass ein Kompartment - Syndrom zu sein , die in intraneuralen Ödem führt, und eine Kompression der Kapillaren die Axone im Sehnerven Versorgung 3. Da die tatsächlich auf das zentrale Nervensystem (ZNS) Trakt ist, kann das Nagetier NAION (rNAION) Modell verwendet werden, um die Mechanismen und Reaktionen auf isolierte CNS weißen Substanz Hübe zu studieren. Das rNAION Modell kann daher sinnvoll sein, viele Probleme in Sezieren zu weißen Substanz mit Schlaganfall im Zusammenhang mit Schäden verbunden. Es kann verwendet werden, um verschiedene neuroprotektive Strategien und Mittel in der weißen Substanz Schlaganfall zu bewerten. Eines der attraktivsten Merkmale des Modells ist, dass esschmerzlos, nicht-invasive Verfahren. Die Laserleistung kann eingestellt werden, um verschiedene Grad der ischämische Schädigung zu erzeugen. Ein weiteres Merkmal ist, dass es auf der laserinduzierten Superoxid-Radikalen beruht, um die Kapillarendothels zu beschädigen, eine progressive Dysfunktion Kapillare zu erzeugen. Es ist diese Funktionsstörungen und progressive Ödeme, die mit dem Mechanismus zu sein bemerkenswert ähnlich angenommen wird, dass NAION verursacht. Die Forschung hat gezeigt , dass es keine direkte kapillare Gerinnungs verursacht, sondern arbeitet durch mindestens zwei Mechanismen: Superoxid - induzierten Tod und Abstreifen eines Teils der kapillaren Endothelzellen 4 und NFkB (nuclear factor kappa-Leichtketten-Enhancer von aktivierten B - Zellen mit) in verbleibenden Endothel Entzündungshochregulierung zugeordnet ist , 5 den Fluidtransport durch die Zellmembranen in das Interstitium erhöht. Die Schließung der Sehnerv Kapillaren und Kompression von interstitieller Flüssigkeit Akkumulationsergebnis in Sehnervenkopf Ischämie verursacht. Ein schematisches Bild gezeigt inFigur 2. Das rNAION Modell kann in beiden Spezies Ratte und Maus 6,7, verwendet werden und kann in der Ebene seiner Schwere variieren, aus einer leichten Läsion zu einem vollständigen, aber schmerzlos Zerstörung des Sehnervs und der Netzhaut, wie beispiels als zentrale Retinaarterienokklusion (ZAV).

<table><tbody><tr><td>50 mW 532 nm laser</td><td>Iridex</td><td></td><td>Standard Ophthalmic Laser</td></tr><tr><td>0 - 100 mW 532 nm laser</td><td>Laserglow technologies</td><td></td><td>Substitute for iridex</td></tr><tr><td>Laser slit lamp adapter</td><td>Iridex</td><td></td><td>SMA coupled adapter for laser output</td></tr><tr><td>Coherent Fieldmate laser meter with thermopile sensor</td><td>Coherent</td><td></td><td>others also appropriate</td></tr><tr><td>Ophthalmic Examing Slit lamp biomicroscope</td><td>Various</td><td></td><td>Haag-Streit is the best; cheaper versions available on ebay</td></tr><tr><td>Rose Bengal</td><td>Sigma</td><td>330000-1G</td><td>Photoinducing agent</td></tr><tr><td>Fundus Contact lens or glass cover slip</td><td>custom/Cantor and Nissel (UK)</td><td></td><td>Custom designed planoconvex plastic lens for eye exam and induction</td></tr><tr><td>Tropicamide 1%</td><td></td><td></td><td></td></tr><tr><td>Tamiya polishing compound</td><td>Tamiya, INC</td><td>87068</td><td>polishing contact lens</td></tr><tr><td>2.5% Hypromellose (Goniovisc)/1% Methycellulose</td><td>HUB Pharmaceuticals</td><td></td><td>contact lens coupling agent</td></tr><tr><td>2.5% Neosynephrine Ophthalmic drops</td><td>Alcon labs</td><td></td><td>pupil dilating agent</td></tr><tr><td>Tropicamide 1%</td><td>Alcon labs</td><td></td><td>pupil dilating agent</td></tr><tr><td>0.5% Proparacaine</td><td>Alcon labs</td><td></td><td>topical Anesthetic</td></tr><tr><td>30 G fused needle insulin syringe</td><td>Various</td><td>Various</td><td>for intravenous injection of rose bengal</td></tr><tr><td>Ophthamic Antibiotic ointment with dexamethasone added (Triple antibiotic ointment)</td><td>Various</td><td>Various</td><td>Apply after induciton to minimize corneal scarring</td></tr><tr><td>Heidelberg Corporation Spectral domain-Optical Coherence Tomograph</td><td>Heidelberg Corporation</td><td></td><td>For Optical coherence measurements baseline and post-induction; not essential for induction</td></tr></tbody></table>

the rodent model of nonarteritic anterior ischemic optic neuropathy (rnaion)

Nonarteritic anterior ischemic optic neuropathy (NAION) is a focal ischemic lesion of the optic nerve that affects 1/700 individuals throughout their lifetime. NAION results in optic nerve edema, selective loss of the retinal ganglion cell neurons (RGCs) and atrophy of the optic nerve. A rodent model of NAION that expresses most NAION features and sequelae has been developed, which is applicable to both rats and mice. This model utilizes a focal laser application of 532 nm wavelength to illuminate a photoactive dye, Rose Bengal (RB), to cause capillary damage and leakage at the targeted anterior optic nerve (the laminar region). After rNAION induction, there is an early optic nerve ischemia, optic nerve edema, and intraneural inflammation, followed by selective RGC and axonal loss. Since the optic nerve is a CNS white matter tract, the rNAION model is applicable to mechanistic studies of selective white matter ischemia, as well as neuroprotective analyses and short and long-term mechanisms of glial and neuronal response to ischemia.

<html> Die Kontaktlinse freigegeben zentralen Netzhaut Visualisierung (Abbildung 1). Der Schwerpunkt Laserspot beleuchtet die Papille auf der Rückseite der Netzhaut (Abbildung 2). Die normale un induzierter Netzhaut wird durch Spaltlampen - Biomikroskop (3A) und SD-OCT (3B und 3C) abgebildet gezeigt. Beim Laserinduktion, wenn kein Farbstoff in dem Kreislauf vorhanden ist, wird Laserlicht führen nicht in Gefäß und Plat...

Watch this Scientific Journal Video about The Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy rNAION at JoVE.com

The Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy rNAION

The following report describes how to replicate the rodent model of nonarteritic anterior ischemic optic neuropathy (rNAION), using the appropriate dye, contact lens and laser parameters. We also reveal the appropriate steps for evaluating the rNAION lesion in vivo.

Das Nagetier-Modell der nonarteritic anteriore ischämische Optikusneuropathie (rNAION)

Nonarteritic anterior ischemic optic neuropathy (NAION) is a focal ischemic lesion of the optic nerve that affects 1/700 individuals throughout their ...

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JoVE Journal

Medicine

The Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy (rNAION)

8.9K Aufrufe.  University of Maryland-Baltimore School of Medicine. The following report describes how to replicate the rodent model of nonarteritic anterior ischemic optic neuropathy (rNAION), using the appropriate dye, contact lens and laser parameters. We also reveal the appropriate steps for evaluating the rNAION lesion in vivo.

Serie: The Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy rNAION

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.

Ein Optic Nerve Crush Injury Mausmodell zur retinalen Ganglienzellen Survival Study

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

Forschung

Neurowissenschaften

A Laser-induced Mouse Model of Chronic Ocular Hypertension to Characterize Visual Defects

Glaucoma, frequently associated with elevated intraocular pressure (IOP), is one of the leading causes of blindness. We sought to establish a mouse model of ocular hypertension to mimic human high-tension glaucoma. Here laser illumination is applied to the corneal limbus to photocoagulate the aqueous outflow, inducing angle closure. The changes of IOP are monitored using a rebound tonometer before and after the laser treatment. An optomotor behavioral test is used to measure corresponding changes in visual capacity. The representative result from one mouse which developed sustained IOP elevation after laser illumination is shown. A decreased visual acuity and contrast sensitivity is observed in this ocular hypertensive mouse. Together, our study introduces a valuable model system to investigate neuronal degeneration and the underlying molecular mechanisms in glaucomatous mice.

Chronic ocular hypertension is induced using laser photocoagulation of the trabecular meshwork in mouse eyes. The intraocular pressure (IOP) is elevated for several months after laser treatment. The decrease of visual acuity and contrast sensitivity of experimental animals are monitored using the optomotor test.

Ein Laser-induzierten Maus-Modell der chronischen Ocular Hypertension zu Sehfehler Charakterisierung

Glaucoma, frequently associated with elevated intraocular pressure (IOP), is one of the leading causes of blindness. We sought to establish a mouse model ...

Medizin

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.

Rattenmodell der photochemisch-induzierte Posterior ischämische Optikusneuropathie

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

A Mouse Model for Laser-induced Choroidal Neovascularization

The mouse laser-induced choroidal neovascularization (CNV) model has been a crucial mainstay model for neovascular age-related macular degeneration (AMD) research. By administering targeted laser injury to the RPE and Bruch&#8217;s membrane, the procedure induces angiogenesis, modeling the hallmark pathology observed in neovascular AMD. 
First developed in non-human primates, the laser-induced CNV model has come to be implemented into many other species, the most recent of which being the mouse. Mouse experiments are advantageously more cost-effective, experiments can be executed on a much faster timeline, and they allow the use of various transgenic models. The miniature size of the mouse eye, however, poses a particular challenge when performing the procedure. Manipulation of the eye to visualize the retina requires practice of fine dexterity skills as well as simultaneous hand-eye-foot coordination to operate the laser. However, once mastered, the model can be applied to study many aspects of neovascular AMD such as molecular mechanisms, the effect of genetic manipulations, and drug treatment effects. 
The laser-induced CNV model, though useful, is not a perfect model of the disease. The wild-type mouse eye is otherwise healthy, and the chorio-retinal environment does not mimic the pathologic changes in human AMD. Furthermore, injury-induced angiogenesis does not reflect the same pathways as angiogenesis occurring in an age-related and chronic disease state as in AMD.
Despite its shortcomings, the laser-induced CNV model is one of the best methods currently available to study the debilitating pathology of neovascular AMD. Its implementation has led to a deeper understanding of the pathogenesis of AMD, as well as contributing to the development of many of the AMD therapies currently available.

Here, we present the mouse laser-induced choroidal neovascularization (CNV) protocol, an experimental model that re-creates the vascular hallmarks of neovascular age-related macular degeneration (AMD). Once mastered, it can reliably and effectively induce CNV as a model system to test various experimental measures.

Ein Mausmodell für Laser-induzierten CNV

The mouse laser-induced choroidal neovascularization (CNV) model has been a crucial mainstay model for neovascular age-related macular degeneration (AMD) ...

Glaucoma-inducing Procedure in an In Vivo Rat Model and Whole-mount Retina Preparation

Glaucoma is a disease of the central nervous system affecting retinal ganglion cells (RGCs). RGC axons making up the optic nerve carry visual input to the brain for visual perception. Damage to RGCs and their axons leads to vision loss and/or blindness. Although the specific cause of glaucoma is unknown, the primary risk factor for the disease is an elevated intraocular pressure. Glaucoma-inducing procedures in animal models are a valuable tool to researchers studying the mechanism of RGC death. Such information can lead to the development of effective neuroprotective treatments that could aid in the prevention of vision loss. The protocol in this paper describes a method of inducing glaucoma - like conditions in an in vivo rat model where 50 &#181;l of 2 M hypertonic saline is injected into the episcleral venous plexus. Blanching of the vessels indicates successful injection. This procedure causes loss of RGCs to simulate glaucoma. One month following injection, animals are sacrificed and eyes are removed. Next, the cornea, lens, and vitreous are removed to make an eyecup. The retina is then peeled from the back of the eye and pinned onto sylgard dishes using cactus needles. At this point, neurons in the retina can be stained for analysis. Results from this lab show that approximately 25% of RGCs are lost within one month of the procedure when compared to internal controls. This procedure allows for quantitative analysis of retinal ganglion cell death in an in vivo rat glaucoma model.

Glaucoma-inducing Procedure in an In Vivo Rat Model and Whole-mount Retina Preparation

Glaucoma is characterized by damage to retinal ganglion cells. Inducing glaucoma in animal models can provide insight into the study of this disease. Here, we outline a procedure that induces loss of RGCs in an in vivo rat model and demonstrates the preparation of whole-mount retinas for analysis.

Glaucoma auslösende Verfahren in ein<em&gt; In Vivo</em&gt; Rat Modell und Whole-mount Retina Vorbereitung

Glaucoma is a disease of the central nervous system affecting retinal ganglion cells (RGCs). RGC axons making up the optic nerve carry visual input to the ...

A Mouse Model of Retinal Ischemia-Reperfusion Injury Through Elevation of Intraocular Pressure

Retinal ischemia-reperfusion (I/R) is a pathophysiological process contributing to cellular damage in multiple ocular conditions, including glaucoma, diabetic retinopathy, and retinal vascular occlusions. Rodent models of I/R injury are providing significant insights into mechanisms and treatment strategies for human I/R injury, especially with regard to neurodegenerative damage in the retinal neurovascular unit. Presented here is a protocol for inducing retinal I/R injury in mice through elevation of intraocular pressure (IOP). In this protocol, the ocular anterior chamber is cannulated with a needle, through which flows the drip of an elevated saline reservoir. Using this drip to raise IOP above systolic arterial blood pressure, a practitioner temporarily halts inner retinal blood flow (ischemia). When circulation is reinstated (reperfusion) by removal of the cannula, severe cellular damage ensues, resulting ultimately in retinal neurodegeneration. Recent studies demonstrate inflammation, vascular permeability, and capillary degeneration as additional elements of this model. Compared to alternative retinal I/R methodologies, such as retinal arterial ligation, retinal I/R injury by elevated IOP offers advantages in its&#160;anatomical specificity, experimental tractability, and technical accessibility, presenting itself as a valuable tool for examining neuronal pathogenesis and therapy in the retinal neurovascular unit.

This article describes a procedure for inducing retinal ischemia-reperfusion injury by elevated intraocular pressure in mice. Retinal ischemia-reperfusion injury by elevated intraocular pressure serves to model human pathologies characterized by compromised oxygen and nutrient delivery in the retina, enabling researchers to examine potential cellular mechanisms and treatments for human diseases of the retinal neurovascular unit.

Ein Maus-Modell der Netzhautischämie-Reperfusionsschaden Durch Erhöhung des intraokularen Druck

Retinal ischemia-reperfusion (I/R) is a pathophysiological process contributing to cellular damage in multiple ocular conditions, including glaucoma, ...

Partial Optic Nerve Transection in Rats: A Model Established with a New Operative Approach to Assess Secondary Degeneration of Retinal Ganglion Cells

Previous studies have shown that the secondary degeneration of retinal ganglion cells (RGCs) occurs commonly in glaucoma. Partial optic nerve transection is considered a useful and reproducible model. Compared with other optic nerve injury models used commonly for assessing secondary degeneration, e.g. complete optic nerve transection and optic nerve crush models, the partial optic nerve transection model is superior as it distinguishes primary from secondary degeneration in situ. Therefore, it serves as an excellent tool for evaluating secondary degeneration. This study describes a novel operative approach of partial optic nerve transection by directly accessing the area of the retrobulbar optic nerve through the orbital lateral wall of the eyeball. Moreover, we present a newly designed, low cost surgical instrument to assist with transection. As demonstrated by the representative results in distinguishing the boundary of primary and secondary injury areas, the new approach and instrument ensures high efficiency and stability of the model by providing adequate space for surgical operation. This in turn makes it easy to separate the meningeal sheath and ophthalmic vessels from the optic nerve before transection. An additional benefit is that this space-saving operative approach improves the investigators&#39; ability to administer drugs, carriers, or selective RGC tracers to the stump of the partially transected optic nerve, allowing the exploration of mechanisms behind secondary injury in RGCs, in a new way.

Secondary degeneration of retinal ganglion cells (RGCs) occurs commonly in glaucoma. This study describes an innovative operative approach for partial optic nerve transection. The use of this space-saving operative approach extends the model's application range, and allows exploration of secondary injury mechanisms in RGCs in a new way.

Partielle Sehnerv Durchtrennung bei Ratten: ein Modell gegründet mit einem neuen operativen Ansatz zur sekundären Degeneration der retinalen Ganglienzellen bewerten

Previous studies have shown that the secondary degeneration of retinal ganglion cells (RGCs) occurs commonly in glaucoma. Partial optic nerve transection ...

Oxygen-Induced Retinopathy Model for Ischemic Retinal Diseases in Rodents

One of the commonly used models for ischemic retinopathies is the oxygen-induced retinopathy (OIR) model. Here we describe detailed protocols for the OIR model induction and its readouts in both mice and rats. Retinal neovascularization is induced in OIR by exposing rodent pups either to hyperoxia (mice) or alternating levels of hyperoxia and hypoxia (rats). The primary readouts of these models are the size of neovascular (NV) and avascular (AVA) areas in the retina. This preclinical in vivo model can be used to evaluate the efficacy of potential anti-angiogenic drugs or to address the role of specific genes in the retinal angiogenesis by using genetically manipulated animals. The model has some strain and vendor specific variation in the OIR induction which should be taken into consideration when designing the experiments.

Oxygen-induced retinopathy (OIR) can be used to model ischemic retinal diseases such as retinopathy of prematurity and proliferative diabetic retinopathy and to serve as a model for proof-of-concept studies in evaluating antiangiogenic drugs for neovascular diseases. OIR induces robust and reproducible neovascularization in the retina that can be quantified.

Sauerstoffinduzierte Retinopathie-Modell für ischämische Netzhauterkrankungen bei Nagetieren

One of the commonly used models for ischemic retinopathies is the oxygen-induced retinopathy (OIR) model. Here we describe detailed protocols for the OIR ...

Full-Circle Cauterization of Limbal Vascular Plexus for Surgically Induced Glaucoma in Rodents

Glaucoma, the second leading cause of blindness worldwide, is a heterogeneous group of ocular disorders characterized by structural damage to the optic nerve and retinal ganglion cell (RGC) degeneration, resulting in visual dysfunction by interrupting the transmission of visual information from the eye to the brain. Elevated intraocular pressure is the most important risk factor; thus, several models of ocular hypertension have been developed in rodents by either genetic or experimental approaches to investigate the causes and effects of the disease. Among those, some limitations have been reported such as surgical invasiveness, inadequate functional assessment, requirement of extensive training, and highly variable extension of retinal damage. The present work characterizes a simple, low-cost, and efficient method to induce ocular hypertension in rodents, based on low-temperature, full-circle cauterization of the limbal vascular plexus, a major component of aqueous humor drainage. The new model provides a technically easy, noninvasive, and reproducible subacute ocular hypertension, associated with progressive RGC and optic nerve degeneration, and a unique post-operative clinical recovery rate that allows in vivo functional studies by both electrophysiological and behavioral methods.

The goal of this protocol is to characterize a novel model of glaucomatous neurodegeneration based on 360&#176; thermic cauterization of limbal vascular plexus, inducing subacute ocular hypertension.

Vollkreiskauterisierung des limbalen Gefäßplexus bei chirurgisch induziertem Glaukom bei Nagetieren

Glaucoma, the second leading cause of blindness worldwide, is a heterogeneous group of ocular disorders characterized by structural damage to the optic ...

A Murine Model of Ischemic Retinal Injury Induced by Transient Bilateral Common Carotid Artery Occlusion

Diverse vascular diseases such as diabetic retinopathy, occlusion of retinal veins or arteries and ocular ischemic syndrome can lead to retinal ischemia. To investigate pathological mechanisms of retinal ischemia, relevant experimental models need to be developed. Anatomically, a main retinal blood supplying vessel is the ophthalmic artery (OpA) and OpA originates from the internal carotid artery of the common carotid artery (CCA). Thus, disruption of CCA could effectively cause retinal ischemia. Here, we established a mouse model of retinal ischemia by transient bilateral common carotid artery occlusion (tBCCAO) to tie the right CCA with 6-0 silk sutures and to occlude the left CCA transiently for 2 seconds via a clamp, and showed that tBCCAO could induce acute retinal ischemia leading to retinal dysfunction. The current method reduces reliance on surgical instruments by only using surgical needles and a clamp, shortens occlusion time to minimize unexpected animal death, which is often seen in mouse models of middle cerebral artery occlusion, and maintains reproducibility of common retinal ischemic findings. The model can be utilized to investigate the pathophysiology of ischemic retinopathies in mice and further can be used for in vivo drug screening.

Here, we describe a mouse model of retinal ischemia by transient bilateral common carotid artery occlusion using simple sutures and a clamp. This model can be useful for understanding the pathological mechanisms of retinal ischemia caused by cardiovascular abnormalities.

Ein murines Modell der ischämischen Netzhautverletzung induziert durch transiente bilaterale gemeinsame Carotis ArterieNverschluss

Diverse vascular diseases such as diabetic retinopathy, occlusion of retinal veins or arteries and ocular ischemic syndrome can lead to retinal ischemia. ...