Name: glutamate and hypoxia as a stress model for the isolated perfused vertebrate retina
Uploaded: 2015-03-22T15:00:00.000+00:00
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Description: Watch this Scientific Journal Video about Glutamate and Hypoxia as a Stress Model for the Isolated Perfused Vertebrate Retina at JoVE.com

This paper is dedicated to my beloved wife Maren and our little Karl.

ウシ目の調製<ol><li>動物が屠殺された直後に牛の目を入手します。 </li><li> 120のNaCl、2のKCl、0.1のMgCl 2、0.15のCaCl 2、1.5 mMののNaH 2 PO 4、13.5のNa 2 HPO 4および5 mMグルコースでを含む特別な媒体」Sickel-ソリューション」で保護された目を輸送RT。 </li><li>暗赤色灯と暗順応条件下での網膜の準備を行います。 </li><li>眼の前の部分を削除します。赤道切開CAを実行します角膜輪部に4ミリメートルの後部。その後、1枚で角膜、虹彩、毛様体およびレンズを取り外します。 Sickel-溶液中の網膜にしてください。 </li><li>機械的に網膜表面にガラス質の添付ファイルを緩め、オープンアイカップから硝子体を除去する。 </li><li>その後4つの象限に目を分割し、約ラウンド領域をパンチアウトトレフィンを使用して直径7mm。 </li><li>静かに網膜を分離色素上皮から、光から保護ボックス内部の記録装置の上に置きます。記録装置は、中央にメッシュプラスチックメンテナで構成されています。メッシュ上に、網膜を配置し、電極上に直接プラスチックリングで固定します。 NOTE：プラスチックメンテ媒体の一定の流れを可能にするために二つのチャンネルを有している。 </li></ol> 2.録音電図（ERG） <ol><li> 、電位図を記録する網膜の両側にある銀/塩化銀電極を使用し、約一定の灌流速度で網膜を灌流するために1ml /分、37℃の一定温度。酸素で飽和した「Sickel-ソリューション」を使用してください。 </li><li>測定を開始する前に、暗い網膜を適応させる（すべての測定中に光から保護する）と、5分の刺激間隔を使用しています。網膜表面で6.3 MLXに設定された強度で刺激のための1 Hzの単一の白色キセノンフラッシュを使用してください。 </LI&gt; <li>使用は、最適な応答を得るために、減光フィルタ、タイマによって制御さ10マイクロ秒の光刺激をキャリブレート。 </li><li>グラスRPS312RMアンプを使用して（100Hzのハイパスフィルタ、50 Hzのノッチフィルタ100,000のx増幅）を測定し、処理したデータを、ERGをフィルタリングして増幅した。信号を乱す可能性のある妨害の周波数をフィルタリングしてみてください。データを処理するために、デスクトップコンピュータ（PC互換性のある）のアナログ·デジタルデータ収集ボードを使用する。 </li><li>安定b波振幅が記録されるまで一定の灌流下暗順応期間の後、電気信号​​の振幅を測定する。 注：5つの測定値が平均値に達し、10％未満を逸脱した場合には、振幅が安定しているとみなされる。単一の測定値の良い例は、 図1に示されている。 </li><li>テストを開始するには、純粋な窒素で純酸素を交換する（単一の実験の数、n = 5）の低酸素状態をテストするまたは250μmのグルタミン酸（n = 5）であった。 </li><li>電気的応答45分間5分毎に記録します。 </li><li>テスト期間の後、75分間酸素で飽和した標準培地で網膜を灌流し、b波振幅の変化を見てください。これはウォッシュアウトフェーズです。 b波のピークまでのA波の谷からb波の振幅を測定します。 </li><li>暗順応条件下で、感光体電位に対する低酸素またはグルタミン酸の効果を調べるために、栄養液に1mMのを追加することによってb波を抑制する。 </li><li> 30分間の安定した感光体の電位を記録した後、1mMのアスパラギン異なる洗浄溶液に網膜45分​​間さらす前と同様の手順を行う。前述のように同じ休薬期間（ステップ2.8）を使用します。 </li></ol> 3.データ分析<ol><li>統計的データを評価するために、 例えば、コルモゴロフ-スミルノフを使用して、すべてのデータのための正規分布を確実にするテスト15。 </li><li>博覧会の前に最後の測定と比較して露光段階後の割合でA及びB波の振幅の減少を計算します。 45分後にERG-振幅の減少を比較する - 展示期間の終わり - ERGへの適用前に測定した。 </li><li>可能な回復を調べるために博覧会前に、対応する振幅にウォッシュアウトフェーズの終了時にA-とB-波の比較。 </li><li>統計分析のために、ソフトウェアJMP統計ソフトウェアまたはSPSSソフトウェアを使用しています。平均±標準偏差として全体のデータを計算します。適切な統計的検定によって有意性を推定します。 注：これらのテストは、実験的な範囲に応じて異なる場合があります。この設定では、スチューデントのt検定を使用しています。 </li></ol>

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The authors have nothing to disclose.

本研究では、低酸素症の45分後にb波の振幅に有意な影響が見られた。この減少は、依然としてウォッシュアウト段階の後に有意であった。感光性に関する同様の効果が観察された。 結果は、他の公開されたデータ16でサポートされているし、私たちに低酸素症の後の可能な神経保護効果を研究する機会を与えている。 250μMのグルタミン酸の4...

神経保護は、過去数十年で眼科研究の調査の強い分野となっている。網膜は、酸素化に大きく依存し、その周囲の細胞の代謝によって強く影響され、高感度の神経回路網である。神経細胞の損傷に関連する主な眼の病状は、網膜血管閉塞、緑内障、および網膜剥離である。 網膜動脈閉塞は網膜血管閉塞のための例として、内側網膜1の低酸素状態に視力の突然の損失につながる。それは、多くの場合、一般的な血管の病理2に関連付けられており、患者のわずか8％を大幅に1視力を回復し、永続的な視覚喪失1につながる。動脈の線維素溶解が治療選択肢として提案されているが、利益は、無作為化臨床試験3に示すことができなかった。 緑内障と網膜剥離両方のグルタミン酸濃度4-6の増加を持っている。生理学的条件下でグルタミン酸は、全体の中枢神経系全体に興奮トランスミッタと内側の網膜7,8として検出された。上昇グルタミン酸レベルは、緑内障及び網膜剥離5,6においても、増殖性糖尿病性網膜9のみならず発見されている。グルタミン酸の増加は、おそらく、したがって、神経細胞の損傷10の興奮毒性につながり。網膜剥離の網膜（毛様体輪の硝子体切除）上の増殖性糖尿病網膜症の手術のいくつかのケースでは、ほとんどの場合必要です。扁平部の硝子体切除機械的操作時には、光ファイバーや長い操作中に灌漑ソリューションの高流量によって発揮されるせん断応力の明るい光が網膜11,12に追加のストレスを発揮する。 すべての疾患は、病理がレチンに局在している点で共通している単独および感覚神経系として網膜を保護する方法を見つけるという課題に眼科コミュニティをもたらす。 電図（ERG）は、インビボで光受容体機能（波）と内網膜（b波）の機能を評価するための標準的な方法である。 ERGは、角膜内に導入銀電極で測定され、眼は、ロッドまたは円錐または内側の網膜の欠陥を検出するための光のレベルの増加によって刺激されている。網膜における異なる欠陥は、振幅（応答の強さ）またはERGの待ち時間（時間 - 応答間隔）の変化によって検出することができる。異なるERGプロトコルと測定方法（パターン-ERG、多焦点-ERGまたは明視野ERG）は、欠陥のさらなる差別化を可能にする。単離された網膜の技術により、試験動物の例からの干渉なしで、網膜への影響を評価すること、最近導入された一般的な反応は13,14。 評価および灌流孤立網膜上の低酸素症およびグルタミン酸ストレスのために定義され、標準化された応力モデルを紹介するこの研究の目的だった。したがって、私たちは、特定の薬剤または眼内灌漑ソリューションの神経保護効果に関する今後の研究のための基礎を築くことを望んでいます。

<table><tbody><tr><td>120 mM NaCl&amp;nbsp;</td><td>Merck Pharma, Germany</td><td>1,064,041,000</td><td></td></tr><tr><td>2 mM KCl,&amp;nbsp;&amp;nbsp;</td><td>Merck Pharma, Germany</td><td>1,050,010,250</td><td></td></tr><tr><td>0.1 mM MgCl2,&amp;nbsp;</td><td>Merck Pharma, Germany</td><td>58,330,250</td><td></td></tr><tr><td>0.15 mM CaCl2</td><td>Merck Pharma, Germany</td><td>111 TA106282</td><td></td></tr><tr><td>1.5 mM NaH2PO4/13.5 mM Na2HPO4&amp;nbsp;&amp;nbsp;</td><td>Merck Pharma, Germany</td><td>1,065,860,500</td><td></td></tr><tr><td>5 mM glucose</td><td>Merck Pharma, Germany</td><td>40,741,000</td><td></td></tr></tbody></table>

glutamate and hypoxia as a stress model for the isolated perfused vertebrate retina

神経保護は、過去数十年で眼科研究の調査の強い分野きや、緑内障、網膜血管閉塞、網膜剥離、および糖尿病性網膜症などの疾患に影響を与えています。それは、将来の前臨床治療試験のための標準化された応力モデルを紹介する本研究の目的であった。 ウシ網膜を調製し、灌流酸素飽和標準溶液とし、ERGを記録した。安定したB波を記録した後、低酸素（純粋N 2）またはグルタミン酸応力（250μmのグルタミン酸）が45分間に発揮した。単独の光受容体機能に対する効果を調べるために、1mMのアスパラギン酸は、波を得た。 ERG-回復は75分間モニターした。 低酸素症の場合、87.0％の波振幅の減少は45分（ウォッシュアウトP = 0.03の終了後に36.5％の減少）の露出時間の後に（P &lt;0.01）が認められた。さらに、初期のDECR87.23パーセントのb波振幅の容易さは、統計的有意に（p &lt;0.01、ウォッシュアウトの終了時の25.5％の減少はp = 0.03）に達したことを記録した。 250μmのグルタミン酸、1.9％た（p&gt; 0.05）の減少が続く波振幅た（p&gt; 0.05）の最初の7.8％の減少である。 b波振幅た（p &lt;0.01）の83.7％の減少が認められた。 75分のウォッシュアウト後に減少が2.3％（P = 0.62）であった。本研究では、標準化されたストレスモデルは、将来の可能性神経保護効果を同定するために有用であり得ることが示されている。

酸素飽和標準溶液（ 図1AおよびB）と網膜製剤の灌流の1時間後にERG-振幅が安定化し、単一の測定値との間の振幅のより少ない変動を示した。 pHは、浸透圧、温度、及び（低酸素症試験を除く）のpO 2は、すべてのテストのために一定に維持した。 内網膜の信号から光受容体の信号を分離するために、1mMのアスパラギン酸は、b波（ 図1A）を抑制する?...

Watch this Scientific Journal Video about Glutamate and Hypoxia as a Stress Model for the Isolated Perfused Vertebrate Retina at JoVE.com

Glutamate and Hypoxia as a Stress Model for the Isolated Perfused Vertebrate Retina

本研究では、我々は将来の前臨床治療試験のための孤立した灌流ウシ網膜のための標準化された応力モデルをご紹介。 A及びB波振幅によって表さ網膜機能上のいずれかの低酸素（純粋なN 2）またはグルタミン酸ストレス（250μMグルタミン酸）の効果を評価した。

単離された灌流脊椎動物の網膜のためのストレスモデルとしてグルタミン酸および低酸素症

Neuroprotection has been a strong field of investigation in ophthalmological research in the past decades and affects diseases such as glaucoma, retinal ...

glutamate-hypoxia-as-stress-model-for-isolated-perfused-vertebrate

Research

JoVE Journal

Medicine

7.8K ビュー.  University Eye Hospital Tübingen. 本研究では、我々は将来の前臨床治療試験のための孤立した灌流ウシ網膜のための標準化された応力モデルをご紹介。 A及びB波振幅によって表さ網膜機能上のいずれかの低酸素（純粋なN 2）またはグルタミン酸ストレス（250μMグルタミン酸）の効果を評価した。 

ビデオ: Glutamate and Hypoxia as a Stress Model for the Isolated Perfused Vertebrate Retina

Assessment of Vascular Regeneration in the CNS Using the Mouse Retina

The rodent retina is perhaps the most accessible mammalian system in which to investigate neurovascular interplay within the central nervous system (CNS). It is increasingly being recognized that several neurodegenerative diseases such as Alzheimer&#8217;s, multiple sclerosis, and amyotrophic lateral sclerosis present elements of vascular compromise. In addition, the most prominent causes of blindness in pediatric and working age populations (retinopathy of prematurity and diabetic retinopathy, respectively) are characterized by vascular degeneration and failure of physiological vascular regrowth. The aim of this technical paper is to provide a detailed protocol to study CNS vascular regeneration in the retina. The method can be employed to elucidate molecular mechanisms that lead to failure of vascular growth after ischemic injury. In addition, potential therapeutic modalities to accelerate and restore healthy vascular plexuses can be explored. Findings obtained using the described approach may provide therapeutic avenues for ischemic retinopathies such as that of diabetes or prematurity and possibly benefit other vascular disorders of the CNS.

The rodent retina has long been recognized as an accessible window to the brain. In this technical paper we provide a protocol that employs the mouse model of oxygen-induced retinopathy to study the mechanisms that lead to failure of vascular regeneration within the central nervous system after ischemic injury. The described system can also be harnessed to explore strategies to promote regrowth of functional blood vessels within the retina and CNS.

マウス網膜を使用してCNSにおける血管再生の評価

The rodent retina is perhaps the most accessible mammalian system in which to investigate neurovascular interplay within the central nervous system (CNS). ...

神経科学

The Analysis of Neurovascular Remodeling in Entorhino-hippocampal Organotypic Slice Cultures

Ischemic brain injury is among the most common and devastating conditions compromising proper brain function and often leads to persisting functional deficits in the affected patients. Despite intensive research efforts, there is still no effective treatment option available that reduces neuronal injury and protects neurons in the ischemic areas from delayed secondary death. Research in this area typically involves the use of elaborate and problematic animal models. Entorhino-hippocampal organotypic slice cultures challenged with oxygen and glucose deprivation (OGD) are established in&#160;vitro models which mimic cerebral ischemia. The novel aspect of this study is that changes of the brain blood vessels are studied in addition to neuronal changes and the reaction of both the neuronal compartment and the vascular compartment can be compared and correlated. The methods presented in this protocol substantially broaden the potential applications of the organotypic slice culture approach. The induction of OGD or hypoxia alone can be applied by rather simple means in organotypic slice cultures and leads to reliable and reproducible damage in the neural tissue. This is in stark contrast to the complicated and problematic animal experiments inducing stroke and ischemia in vivo. By broadening the analysis to include the study of the reaction of the vasculature could provide new ways on how to preserve and restore brain functions. The slice culture approach presented here might develop into an attractive and important tool for the study of ischemic brain injury and might be useful for testing potential therapeutic measures aimed at neuroprotection.

A protocol for entorhino-hippocampal organotypic slice cultures, which allows reproducing many aspects of ischemic brain injury, is presented. By studying changes of the neurovasculature in addition to changes in the neurons, this protocol is a versatile tool to study plastic changes in neural tissue after injury.

Entorhino海馬器官型スライス培養における神経血管リモデリングの解析

Ischemic brain injury is among the most common and devastating conditions compromising proper brain function and often leads to persisting functional ...

Oxygen-Glucose Deprivation and Reoxygenation as an In Vitro Ischemia-Reperfusion Injury Model for Studying Blood-Brain Barrier Dysfunction

Ischemia-Reperfusion (IR) injury is known to contribute significantly to the morbidity and mortality associated with ischemic strokes. Ischemic cerebrovascular accidents account for 80% of all strokes. A common cause of IR injury is the rapid inflow of fluids following an acute/chronic occlusion of blood, nutrients, oxygen to the tissue triggering the formation of free radicals.
Ischemic stroke is followed by blood-brain barrier (BBB) dysfunction and vasogenic brain edema. Structurally, tight junctions (TJs) between the endothelial cells play an important role in maintaining the integrity of the blood-brain barrier (BBB). IR injury is an early secondary injury leading to a non-specific, inflammatory response. Oxidative and metabolic stress following inflammation triggers secondary brain damage including BBB permeability and disruption of tight junction (TJ) integrity.
Our protocol presents an in vitro example of oxygen-glucose deprivation and reoxygenation (OGD-R) on rat brain endothelial cell TJ integrity and stress fiber formation. Currently, several experimental in vivo models are used to study the effects of IR injury; however they have several limitations, such as the technical challenges in performing surgeries, gene dependent molecular influences and difficulty in studying mechanistic relationships. However, in vitro models may aid in overcoming many of those limitations. The presented protocol can be used to study the various molecular mechanisms and mechanistic relationships to provide potential therapeutic strategies. However, the results of in vitro studies may differ from standard in vivo studies and should be interpreted with caution.

Oxygen-Glucose Deprivation and Reoxygenation as an In Vitro Ischemia-Reperfusion Injury Model for Studying Blood-Brain Barrier Dysfunction

Ischemia-Reperfusion (IR) injury is associated with a high rate of morbidity and mortality. The goal of the in vitro model of oxygen-glucose deprivation and reoxygenation (OGD-R) described here is to assess the effects of ischemia reperfusion injury on a variety of cells, particularly in blood-brain barrier (BBB) endothelial cells.

などの酸素グルコース欠乏および再酸素化<em&gt;インビトロ</em&gt;虚血再灌流傷害モデル血液脳関門の機能障害を研究するための

Ischemia-Reperfusion (IR) injury is known to contribute significantly to the morbidity and mortality associated with ischemic strokes. Ischemic ...

医学

Methodology for Biomimetic Chemical Neuromodulation of Rat Retinas with the Neurotransmitter Glutamate In Vitro

Photoreceptor degenerative diseases cause irreparable blindness through the progressive loss of photoreceptor cells in the retina. Retinal prostheses are an emerging treatment for photoreceptor degenerative diseases that seek to restore vision by artificially stimulating the surviving retinal neurons in the hope of eliciting comprehensible visual perception in patients. Current retinal prostheses have demonstrated success in restoring limited vision to patients using an array of electrodes to electrically stimulate the retina but face substantial physical barriers in restoring high acuity, natural vision to patients. Chemical neurostimulation using native neurotransmitters is a biomimetic alternative to electrical stimulation and could bypass the fundamental limitations associated with retinal prostheses using electrical neurostimulation. Specifically, chemical neurostimulation has the potential to restore more natural vision with comparable or better visual acuities to patients by injecting very small quantities of neurotransmitters, the same natural agents of communication used by retinal chemical synapses, at much finer resolution than current electrical prostheses. However, as a relatively unexplored stimulation paradigm, there is no established protocol for achieving chemical stimulation of the retina in vitro. The purpose of this work is to provide a detailed framework for accomplishing chemical stimulation of the retina for investigators who wish to study the potential of chemical neuromodulation of the retina or similar neural tissues in vitro. In this work, we describe the experimental setup and methodology for eliciting retinal ganglion cell (RGC) spike responses similar to visual light responses in wild-type and photoreceptor-degenerated wholemount rat retinas by injecting controlled volumes of the neurotransmitter glutamate into the subretinal space using glass micropipettes and a custom multiport microfluidic device. This methodology and protocol are general enough to be adapted for neuromodulation using other neurotransmitters or even other neural tissues.

Methodology for Biomimetic Chemical Neuromodulation of Rat Retinas with the Neurotransmitter Glutamate In Vitro

This protocol describes a novel method for investigating a form of chemical neurostimulation of wholemount rat retinas in vitro with the neurotransmitter glutamate. Chemical neurostimulation is a promising alternative to the conventional electrical neurostimulation of retinal neurons for treating irreversible blindness caused by photoreceptor degenerative diseases.

バイオミメティック化学ニューロモデュレーション神経伝達物質グルタミン酸の in Vitroラット網膜のための方法論

Photoreceptor degenerative diseases cause irreparable blindness through the progressive loss of photoreceptor cells in the retina. Retinal prostheses are ...

生物工学

Monitoring Astrocyte Reactivity and Proliferation in Vitro Under Ischemic-Like Conditions

Ischemic stroke is a complex brain injury caused by a thrombus or embolus obstructing blood flow to parts of the brain. This leads to deprivation of oxygen and glucose, which causes energy failure and neuronal death. After an ischemic stroke insult, astrocytes become reactive and proliferate around the injury site as it develops. Under this scenario, it is difficult to study the specific contribution of astrocytes to the brain region exposed to ischemia. Therefore, this article introduces a methodology to study primary astrocyte reactivity and proliferation under an in vitro model of an ischemia-like environment, called oxygen glucose deprivation (OGD). Astrocytes were isolated from 1-4 day-old neonatal rats and the number of non-specific astrocytic cells was assessed using astrocyte selective marker Glial Fibrillary Acidic Protein (GFAP) and nuclear staining. The period in which astrocytes are subjected to the OGD condition can be customized, as well as the percentage of oxygen they are exposed to. This flexibility allows scientists to characterize the duration of the ischemic-like condition in different groups of cells in vitro. This article discusses the timeframes of OGD that induce astrocyte reactivity, hypertrophic morphology, and proliferation as measured by immunofluorescence using Proliferating Cell Nuclear Antigen (PCNA). Besides proliferation, astrocytes undergo energy and oxidative stress, and respond to OGD by releasing soluble factors into the cell medium. This medium can be collected and used to analyze the effects of molecules released by astrocytes in primary neuronal cultures without cell-to-cell interaction. In summary, this primary cell culture model can be efficiently used to understand the role of isolated astrocytes upon injury.

Monitoring Astrocyte Reactivity and Proliferation in Vitro Under Ischemic-Like Conditions

Ischemic stroke is a complex event in which the specific contribution of astrocytes to the affected brain region exposed to oxygen glucose deprivation (OGD) is difficult to study. This article introduces a methodology to obtain isolated astrocytes and study their reactivity and proliferation under OGD conditions.

反応性アストロ サイトと増殖の in Vitro虚血のような条件下での監視

Ischemic stroke is a complex brain injury caused by a thrombus or embolus obstructing blood flow to parts of the brain. This leads to deprivation of ...

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.

眼圧の上昇を通じて、網膜虚血再灌流障害のマウスモデル

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

An Acute Retinal Model for Evaluating Blood Retinal Barrier Breach and Potential Drugs for Treatment

A low-cost, easy-to-use and powerful model system is established to evaluate potential treatments that could ameliorate blood retinal barrier breach. An inflammatory factor, histamine, is demonstrated to compromise vessel integrity in the cultured retina through positive staining of IgG outside of the blood vessels. The effects of histamine itself and those of candidate drugs for potential treatments, such as lipoxin A4, are assessed using three parameters: blood vessel leakage via IgG immunostaining, activation of M&#252;ller cells via GFAP staining and change in neuronal dendrites through staining for MAP2. Furthermore, the layered organization of the retina allows a detailed analysis of the processes of M&#252;ller and ganglion cells, such as changes in width and continuity. While the data presented is with swine retinal culture, the system is applicable to multiple species. Thus, the model provides a reliable tool to investigate the early effects of compromised retinal vessel integrity on different cell types and also to evaluate potential drug candidates for treatment.

A low-cost, easy-to-use and powerful system is established to evaluate potential treatments that could ameliorate blood retinal barrier breach induced by histamine. Blood vessel leakage, M&#252;ller cell activation and the continuity of neuronal processes are utilized to assess the damage response and its reversal with a potential drug, lipoxin A4.

治療のために血液網膜関門の違反と潜在的な薬を評価するための急性網膜モデル

A low-cost, easy-to-use and powerful model system is established to evaluate potential treatments that could ameliorate blood retinal barrier breach. An ...

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.

げっ歯類における虚血性網膜症の酸素誘導網膜症モデル

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

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.

一過性両側性頸動脈閉塞による虚血性筋炎損傷のマウスモデル

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

Retinal Explant of the Adult Mouse Retina as an Ex Vivo Model for Studying Retinal Neurovascular Diseases

One of the challenges in retina research is studying the cross-talk between different retinal cells such as retinal neurons, glial cells, and vascular cells. Isolating, culturing, and sustaining retinal neurons in vitro have technical and biological limitations. Culturing retinal explants may overcome these limitations and offer a unique ex vivo model to study the cross-talk between various retinal cells with well-controlled biochemical parameters and independent of the vascular system. Moreover, retinal explants are an effective screening tool for studying novel pharmacological interventions in various retinal vascular and neurodegenerative diseases such as diabetic retinopathy. Here, we describe a detailed protocol for retinal explants' isolation and culture for an extended period. The manuscript also presents some of the technical problems during this procedure that may affect the desired outcomes and reproducibility of the retinal explant culture. The immunostaining of the retinal vessels, glial cells, and neurons demonstrated intact retinal capillaries and neuroglial cells after 2 weeks from the beginning of the retinal explant culture. This establishes retinal explants as a reliable tool for studying changes in the retinal vasculature and neuroglial cells under conditions that mimic retinal diseases such as diabetic retinopathy.

Retinal Explant of the Adult Mouse Retina as an Ex Vivo Model for Studying Retinal Neurovascular Diseases

This protocol presents and describes steps for the isolation, dissection, culturing, and staining of retinal explants obtained from an adult mouse. This method is beneficial as an ex vivo model for studying different retinal neurovascular diseases such as diabetic retinopathy.

網膜神経血管疾患研究のための ex vivo モデルとしての成体マウス網膜網膜の外植片

One of the challenges in retina research is studying the cross-talk between different retinal cells such as retinal neurons, glial cells, and vascular ...

単離された灌流脊椎動物の網膜のためのストレスモデルとしてグルタミン酸および低酸素症

要約

さらに動画を探す

この動画の章

マウス網膜を使用してCNSにおける血管再生の評価

Entorhino海馬器官型スライス培養における神経血管リモデリングの解析

などの酸素グルコース欠乏および再酸素化

バイオミメティック化学ニューロモデュレーション神経伝達物質グルタミン酸の in Vitroラット網膜のための方法論

反応性アストロサイトと増殖の in Vitro虚血のような条件下での監視

眼圧の上昇を通じて、網膜虚血再灌流障害のマウスモデル

治療のために血液網膜関門の違反と潜在的な薬を評価するための急性網膜モデル

げっ歯類における虚血性網膜症の酸素誘導網膜症モデル

一過性両側性頸動脈閉塞による虚血性筋炎損傷のマウスモデル

網膜神経血管疾患研究のための ex vivo モデルとしての成体マウス網膜網膜の外植片

単離された灌流脊椎動物の網膜のためのストレスモデルとしてグルタミン酸および低酸素症

要約

さらに動画を探す

この動画の章

マウス網膜を使用してCNSにおける血管再生の評価

Entorhino海馬器官型スライス培養における神経血管リモデリングの解析

などの酸素グルコース欠乏および再酸素化

バイオミメティック化学ニューロモデュレーション神経伝達物質グルタミン酸の in Vitroラット網膜のための方法論

反応性アストロ サイトと増殖の in Vitro虚血のような条件下での監視

眼圧の上昇を通じて、網膜虚血再灌流障害のマウスモデル

治療のために血液網膜関門の違反と潜在的な薬を評価するための急性網膜モデル

げっ歯類における虚血性網膜症の酸素誘導網膜症モデル

一過性両側性頸動脈閉塞による虚血性筋炎損傷のマウスモデル

網膜神経血管疾患研究のための ex vivo モデルとしての成体マウス網膜網膜の外植片

反応性アストロサイトと増殖の in Vitro虚血のような条件下での監視