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.
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.
非动脉炎性前部缺血性视神经病(NAION)是视神经(ON)1的前部的局灶性缺血病变。 NAION是在50 2岁以上的个体突然视神经相关的视力丧失的最常见的原因。机理被认为是,其导致神经内水肿一个室综合征,并且使得毛细管视神经内供给轴突压缩3。
因为在ON实际上是一种中枢神经系统(CNS)道,啮齿动物NAION(rNAION)模型可以用于机制和响应研究分离的CNS白质笔。因此,rNAION模型可能在解剖与白质中风相关的损害相关的许多问题非常有用。它可以用来评估在白质行程不同神经保护策略和代理。
之一的模型的最吸引人的特点是,它是无痛,无创的过程。激光功率可被调节,以产生不同程度的局部缺血损伤的。另一个特点是,它依赖于激光诱导超氧自由基损伤毛细血管内皮,产生累进毛细管功能障碍。它是被认为是非常相似的,导致NAION机制此功能障碍和渐进水肿。研究已经表明,它不会导致直接毛细管凝结,但通过至少两种机制工作的:过氧化物诱导的死亡和一些毛细管的剥离内皮细胞4,和激活的B细胞的的NFkB(核因子kappa轻链增强剂)相关的炎症性上调在剩余的内皮,具有增加的跨细胞膜流体输送入间质5。视神经毛细血管受压所致间液积聚导致视神经缺血头的关闭。示意图图片所示图2,rNAION模型可在大鼠和小鼠物种6,7-都可以使用,并可以在其严重性的程度而改变,从轻微损伤视神经的完整,但无痛破坏和视网膜等视网膜中央动脉阻塞(CRAO)。
虽然有若干的视神经损伤(视神经损伤12,视神经横断13和PION 14)的机型,rNAION模型是人性化,适应大鼠和小鼠。它更类似于NAION的人体临床状况。这种情况包括渐进式前视神经水肿,前路视神经骨筋膜室综合征,局灶性脑缺血轴突的,孤立的视网膜神经节细胞轴突的破坏和损失在延长的时间过程。目前报告给出了rNAION感应适当的步骤,诱导期间讨论的潜在问题,并且描述…
The authors have nothing to disclose.
我们感谢谁对这个模型工作的许多学生和研究人员,以提高其有效性,并了解其作用机制。特别感谢博士的。玛丽·约翰逊(马里兰大学巴尔的摩分校),Nitza登堡 – 科恩(施奈德曼儿童医院,佩塔提克瓦-Tikva的,以色列),张朝阳(爱因斯坦医学院,布朗克斯,NY),和Valerie Touitou(总医院Salpetrie,法国巴黎)。这项研究是由RO1 EY015304为SLB部分资助。
50mW 532nm laser | Iridex | Standard Ophthalmic Laser | |
0-100mW 532nm laser | Laserglow technologies | Substitute for iridex | |
Laser slit lamp adapter | Iridex | SMA coupled adapter for laser output | |
Cpherent Fieldmate laser meter with thermopile sensor | Coherent | others also appropriate | |
Ophthalmic Examing Slit lamp biomicroscope | VArious | Haag-Streit is the best; cheaper versions available on ebay | |
Rose Bengal | Sigma | 330000-1G | Photoinducing agent |
Fundus Contact lens or glass cover slip | custom/Cantor and Nissel (UK) | Custom designed planoconvex plastic lens for eye exam and induction | |
Tropicamide 1% | |||
Tamiya polishing compound | Tamiya, INC | 87068 | polishing contact lens |
2.5% Hypromellose (Goniovisc)/1% Methycellulose | HUB Pharmaceuticals | contact lens coupling agent | |
2.5% Neosynephrine Ophthalmic drops | Alcon labs | pupil dilating agent | |
Tropicamide 1% | Alcon labs | pupil dilating agent | |
0.5% Proparacaine | Alcon labs | topical Anesthetic | |
30ga fused needle insulin syringe | Various | Various | for intravenous injection of rose bengal |
Ophthamic Antibiotic ointment with dexamethasone added (Triple antibiotic ointment) | Various | Various | Apply after induciton to minimize corneal scarring |
Heidelberg Corporation Spectral domain-Optical Coherence Tomograph | Heidelberg Corportion | For Optical coherence measurements baseline and post-induction; not essential for induction |