视网膜缺血--再灌注损伤的保护

视网膜缺血-再灌注损伤是目前研究较多的一个课题,其损伤机制复杂,目前通过各种实验研究探索其损伤机制以及减轻或防止缺血-再灌注损伤的药物和方法很多.现就视网膜缺血-再灌注损伤的保护机制进行总结归纳.     

牡荆苷对大鼠视网膜缺血-再灌注损伤模型中神经节细胞的保护作用

目的:探讨牡荆苷对大鼠视网膜缺血-再灌注(RIR)引起的视网膜神经节细胞(RGCs)氧化应激损伤的保护作用及其可能的作用机制。方法:将60只SPF级雄性SD大鼠按照随机数字表法随机分为正常对照组、模型组和牡荆苷组,均以右眼为实验眼。模型组和牡荆苷组大鼠采用前房灌注方法建立RIR模型,牡荆苷组大鼠建模后每日按照25 mg...     

藏红花素对视网膜缺血再灌注损伤小鼠视网膜神经节细胞的保护作用及其机制研究

目的　研究藏红花素对视网膜缺血再灌注损伤（RIRI）小鼠视网膜神经节细胞（RGC）的保护作用及其机制。方法　将144只C57BL/6小鼠随机分为3组:假手术组、模型组、藏红花素治疗组。模型组和藏红花素治疗组小鼠建立RIRI模型,藏红花素治疗组小鼠造模前30 min腹腔注射50 mg·kg^-1藏红花素。RIRI后14 d,视网膜铺片染色比较各组小鼠RGC密度差异。RIRI后24 h,HE染色比较各组小鼠视网膜内层厚度差异。于RIRI后不同时间点（0 h、3 h、6 h、9 h、12 h、15 h）取各组小鼠视网膜组织,通过多重基因定量分析系统检测NLRP3、ASC、Caspase-1、白细胞介素-1β（IL-1β） mRNA的表达变化。RIRI后6 h和12 h取各组小鼠视网膜组织,Western blot检测NLRP3、ASC、Caspase-1、IL-1β蛋白的表达,ELISA检测IL-1β蛋白的含量,并对比分析。结果　小鼠RIRI后14 d,视网膜铺片染色结果显示,藏红花素治疗组较模型组小鼠RGC密度增加约18.5%（P<0.05）。RIRI后24 h,HE染色结果显示,藏红花素治疗组小鼠视网膜内层厚度较模型组显著降低（P<0.01）。多重定量分析系统检测结果显示,RIRI后6 h、9 h及12 h,藏红花素治疗组小鼠视网膜组织中Caspase-1以及IL-1β mRNA表达较模型组均显著降低（均为P<0.05)。Western blot检测结果显示,藏红花素治疗组小鼠视网膜组织中Caspase-1以及IL-1β蛋白表达较模型组均显著降低（均为P<0.05)。RIRI后6 h、12 h,模型组小鼠视网膜组织中NLRP3、ASC mRNA和蛋白表达与假手术组相比无显著变化（均为P>0.05)。ELISA检测结果进一步证实,RIRI后6 h和12 h,藏红花素治疗组小鼠视网膜组织中IL-1β蛋白含量较模型组均显著降低（均为P<0.05)。结论　藏红花素通过抑制Caspase-1和IL-1β表达保护RIRI小鼠RGC。     

Protection of retinal ganglion cells against optic nerve injury by induction of ischemic preconditioning

AIM: To explore if ischemic preconditioning (IPC) can enhance the survival of retinal ganglion cells (RGCs) after optic nerve axotomy. METHODS: Twenty-four hours prior to retinal ischemia 60min or axotomy, IPC was applied for ten minutes in groups of (n=72) animals. The survival of RGCs, the cellular expression of heat shock protein 27 (HSP27) and heat shock protein 70 (HSP70) and the numbers of retinal microglia in the different groups were quantified at 7 and 14d post-injury. The cellular expression of HSP27 and HSP70 and changes in the numbers of retinal microglia were quantified to detect the possible mechanism of the protection of the IPC. RESULTS: Ten minutes of IPC promoted RGC survival in both the optic nerve injury (IPC-ONT) and the retinal ischemia 60min (IPC-IR60) groups, examined at 7d and 14d post-injury. Microglial proliferation showed little correlation with the extent of benefit effects of IPC on the rescue of RGCs. The number of HSP27-positive RGCs was significantly higher in the IPC-ONT group than in the sham IPC-ONT group, although the percentage of HSP27-positive RGCs did not significantly differ between groups. For the IPC-IR60 group, neither the number nor the percentage of the HSP27-positive RGCs differed significantly between the IPC and the sham-operated groups. The number of HSP70-positive RGCs was significantly higher for both the IPC-ONT and the IPC-IR60 experimental groups, but the percentages did not differ. CONCLUSION: The induction of IPC enhances the survival of RGCs against both axotomy and retinal ischemia.     

y-39983预处理对缺血-再灌注损伤大鼠视网膜的保护作用

目的:探讨ROCK抑制剂y-39983对缺血再灌注(ischemia reperfusion,IR)大鼠视网膜的保护作用。方法:SD大鼠60只随机分为正常组(n=15)、IR组(n=15)、生理盐水组(n=15)、y-39983治疗组(n=15)。正常组不做任何处理,后三组制作视网膜IR模型(前房加压灌注法),其中生理盐水组和y-39983治疗组于造模前5min分别向实验眼玻璃体腔内注入无菌生理盐水和y-39983各10μL。采用免疫组化方法检测细胞间黏附分子-1(intercellular cell adhesion molecules-1,ICAM-1)表达。荧光金逆行标记计数各组大鼠视网膜神经节细胞(retinalganglion cells,RGCs)。应用组织病理学方法和视网膜电流图评估视网膜损伤程度。结果:y-39983预处理能降低ICAM-1蛋白表达和视网膜水肿程度,并且显著提高了视网膜神经节细胞存活率及b波和O2相对恢复率,缓解IR损伤所致的内层视网膜变薄的情况。结论:y-39983能减轻视网膜IR损伤,而这一保护效应在一定程度上与其抑制ICAM-1异常表达增加有关,表明y-39983对IR损伤相关的视网膜疾病有治疗作用。     

视网膜缺血再灌注损伤后视网膜神经节细胞pax6的表达变化与意义

【摘要】 目的 探索视网膜缺血再灌注损伤后视网膜神经节细胞pax6的表达变化及意义。 设计 实验研究。研究对象 缺血再灌注损伤大鼠视网膜。方法 成年健康雄性Sprague-Dawley大鼠 30只,随机选取5只作为空白对照组,其余25只为视网膜缺血再灌注损伤组,采用升高右眼眼压的 方法制作视网膜缺血再灌注损伤模型。视网膜缺血再灌注后1、2、4、6、8周分5组,每组5只,不 同时间点取右眼行免疫荧光染色,观察视网膜神经节细胞中pax6表达情况。主要指标 pax6的表达 。结果 视网膜缺血再灌注损伤后随着时间推移视网膜各层逐渐出现pax6表达阳性的细胞,对照组 视网膜神经节细胞pax6表达阳性率为（1.28±1.41）%,损伤后1、2、4、6、8周分别为（0.99± 1.23）%、（14.45±2.72）%、（50.88±4.73）%、（71.00±4.72）%、（78.80±4.62）% （F=1.350,P＜0.0001）。各组与对照组两两比较,缺血后1周视网膜神经节细胞pax6表达阳性率 差异无统计学意义（P=0.835）,缺血再灌注损伤2、4、6、8周视网膜神经节细胞pax6表达阳性率 均明显升高（P均＜0.0001）。结论 视网膜缺血再灌注损伤后视网膜各层均出现pax6表达阳性细胞 ,视网膜缺血再灌注损伤能诱导视网膜内源性干细胞激活。（眼科, 2012, 21： 414-417）     

视网膜神经节细胞的保护和修复

视网膜神经节细胞(RGCs)的进行性死亡是许多视网膜和视神经疾病发展到最后的必经之路。长期以来一直认为，由于抑制性环境的存在，视神经损伤后不能再生和修复，现在研究证实，在特定的条件下，尽管RGCs的胞体或轴突受损，仍能免于死亡，而且变性的轴突能再生，并能与靶组织建立突触联系。对RGCs的保护和修复的研究进展作一综述。     

GM-1对大鼠视网膜缺血再灌注损伤的保护作用

目的 探讨单唾液酸神经节苷脂（monosialoganglioside,GM-1）对大鼠视网膜缺血冉灌注损伤后视网膜组织及超微结构的保护作用.方法 健康成年Wistar大鼠75只,随机分为3组：正常组5只、NS组35只,GM-1组35只.正常对照组不加任何处理因素,NS组和GM-1组通过升高眼压造成视网膜缺血60 min,分别于缺血前12 h、1 h及缺血结束时3次腹腔注射NS 3mL/kg或GM-1 3mL/kg（10 mg/mL）,并于再灌注0 h（单纯缺血后）、1 h、6 h、12 h、24 h、3 d和7 d共7个时间点取双眼眼球,每时间点5只,HE染色观察视网膜组织结构并测量视网膜内层平均厚度（mean thickhess of the inner retinal layers,MTIRL）,透射电镜观察视网膜超微结构变化.结果 缺血再灌注后,内层视网膜依次表现出水肿、凋亡、萎缩的损伤过程.GM-1可明显减轻其水肿和萎缩的程度,并减少凋亡的发生.结论 GM-1对视网膜缺血再灌注损伤具有明确的保护作用,可能是其有效治疗药物.     

米诺环素对大鼠视网膜缺血再灌注的保护作用探讨

目的 探讨米诺环索对大鼠视网膜缺血再灌注损伤的保护作用.方法 SD大鼠88只,分为正常对照组8只,缺血组和治疗组各40只.建立视网膜缺血再灌注模型,于6、24、48、72 h检测视网膜电图(ERG)b波振幅,分光光度计测定超氧化物歧化酶(SOD),丙二醛(MDA),一氧化氮(NO)的变化,免疫组织化学检测半胱天冬酶-3(caspase-3)的表达,电镜观察超微结构.结果 与缺血组相比,治疗组可维持ERG b波振幅,升高SOD含量,降低MDA、NO含量,降低caspase-3表达,可减轻超微结构损伤(P＜0.05).结论 米诺环素可维持ERG b波振幅,调控SOD、MDA、NO,改善超微结构而保护视网膜.     

SIRT1 is required for the neuroprotection of resveratrol on retinal ganglion cells after retinal ischemia-reperfusion injury in mice

Graefe's Archive for Clinical and Experimental Ophthalmology - Retinal ganglion cells (RGCs) loss is closely related to visual impairment in glaucoma, so the neuroprotection on RGCs is...     

青光眼视网膜节细胞损伤的研究进展

青光眼是一种主要的致盲眼病,随着对青光眼研究的深入,逐渐认为高眼压和/或缺血造成视网膜节细胞(retinal ganglion cells,RGCs)以凋亡的方式不断丢失,而神经营养因子、谷氨酸、NO、自由基及Ca2+的浓度变化参与了RGCs的凋亡过程。我们通过本文综述了参与青光眼RGCs损伤的几种因素。     

Protection by eliprodil against excitotoxicity in cultured rat retinal ganglion cells

PURPOSE: To test whether eliprodil (SL 82.0715), a unique antagonist for the N-methyl-D-aspartate (NMDA) receptor, is protective in the glutamate-induced cytotoxicity model in cultured rat retinal ganglion cells (RGCs). METHODS: Two to four days after a fluorescent dye, Di-I, was injected near the superior colliculi, neonatal rats were killed, and retinal cells were dissociated and cultured. Survival of RGCs after drug treatment was assayed by counting Di-I fluorescent cells. RESULTS: In rat RGCs, glutamate-induced toxicity with a mean EC50 of 10.7 microM. Only 47% of RGCs survived after a 3-day treatment with 100 microM glutamate. Studies using selective agonists and antagonists indicated that the glutamate-induced toxicity was mediated largely by the NMDA receptor. Pretreatment with eliprodil protected against such toxicity. Eliprodil exhibited a mean IC50 of 1.0 nM (log [IC50] = -9.00 +/- 0.01, mean +/- SEM, n = 3; against cell death produced by 100 microM glutamate). At 1 microM, eliprodil was maximally protective; cell survival in the presence of 100 microM glutamate challenge was 100% +/- 5% (n = 3). This protective effect of eliprodil may be related to its reduction (by 78%) of NMDA-induced currents recorded under patch-clamp recording in these cells. CONCLUSIONS: Eliprodil is protective against glutamate cytotoxicity in retinal neurons. It may be a useful novel compound for the treatment of retinopathies including glaucoma in which excitotoxicity has been implicated.     

银杏叶提取物对急性缺血再灌注后视网膜神经节细胞的保护作用

目的探讨银杏叶提取物（EGb761）对大鼠急性高眼压诱导缺血再灌注模型中视网膜神经节细胞（RGCs）的保护作用。方法60只SD大鼠随机分为5组,右眼为损伤眼,行前房穿刺灌注形成110mmHg的眼压维持60min,左眼未损伤,作为空白对照。损伤后2h及此后每日1次灌胃给药,各组分别给予生理盐水5mg／kg、1％灯盏细辛5mg／kg、0．25％EGb761 5mg／kg、1％EGb7615mg／kg和4％EGb761 5mg／kg。动物损伤后第23天用荧光金行双上丘逆行标记,第28天取眼球标本做视网膜铺片并拍摄照片,计数RGCs并计算其的存活率。结果生理盐水组、1％灯盏细辛组、0．25％EGb761、1％EGb761和4％EGb761组RGCs存活率分别为66．58％、75．62％、74．92％、76．57％、79．87％。生理盐水组与各EGb761组之间差异均有统计学意义（q=0．00,q=0．19,q=0．10,P〈0．01）,不同质量浓度EGb761组之间差异均无统计学意义（q=0．22,q=0．13,q=0．45,P〉0．05）;1％灯盏细辛组与生理盐水对照组比较差异有统计学意义（q=0．16,P=0．02）,与0．25％EGb761组、1％EGb761组、4％EGb761组比较差异均无统计学意义（q=0．20,q=0．01,q=0．50,P〉0．05）。结论在急性高眼压诱导缺血再灌注模型中,银杏叶提取物能有效地保护RGCs。     

复方樟柳碱对大鼠视网膜缺血再灌注损伤的保护作用

目的:探讨复方樟柳碱对大鼠视网膜缺血再灌注损伤的治疗作用。方法:将成年雌性Wistar大鼠随机分成正常对照组,造模组和复方樟柳碱组,每组10只。采用前房灌注升高眼压制作急性视网膜缺血模型。观察1,3,7d视网膜电图a波b波的恢复情况。每组随机取2只大鼠造模眼球光镜、电镜下观察视网膜形态结构的变化,以及神经节细胞线粒体的变化。结果:复方樟柳碱组较造模组神经节细胞线粒体肿胀程度轻,b波明显恢复,同造模组与正常组间b波的恢复比较差异有显著统计学意义(P<0.01)。结论:复方樟柳碱可减轻大鼠视网膜缺血再灌注损伤,有神经细胞保护作用。     

Development and role of retinal glia in regeneration of ganglion cells following retinal injury.

AIMS/BACKGROUND: Recent observations have shown that the glial scar resulting from a surgical lesion of the immature retina differs from elsewhere in the central nervous system, in that it permits the through growth and reconnection of regenerating axons. This study in the opossum examines in detail the development and reaction to injury of retinal glia at different developmental stages, and specifically examines the distribution of the gliosis related inhibitory molecule, chondroitin sulphate proteoglycan (CSPG), making comparisons with a control site of gliosis in the cerebral cortex. METHODS: A linear slit was cut into the retina or cortex with a fine tungsten probe. After a variable time delay, immunocytochemistry of the resulting gliosis was employed to detect astrocytes with glial fibrillary acidic protein (GFAP), Müller cells with vimentin, and CSPG with CS-56 antibodies. GFAP was also used at different ages to examine the normal development of astrocytes in the retina of this species. RESULTS: Astrocytes entered the retina 12 days after birth (P12), closely associated with blood vessels in the nerve fibre layer. In experiments at all ages studied, cellular continuity was re-established across the lesioned retina, which did not result in a significant astrocyte proliferation or CSPG expression. In contrast, cortical injury led to the development of a cystic cavity surrounded by astrocytes and CSPG. Müller cells expressed GFAP but not CSPG in the lesioned retina. CONCLUSION: Successful regrowth of ganglion cells through a retinal lesion may be partly the result of the scarcity of astrocytes in the retina, which results in minimal gliosis, or of their apparent inability to express inhibitory molecules.     

NMDA受体甘氨酸位点拮抗剂Y1231对视网膜缺血再灌注损伤后RGCs的影响

目的 研究NMDA受体甘氨酸位点拮抗剂Y1231对视网膜缺血再灌注损伤后神经节细胞的影响.方法 采用视网膜神经节细胞(RGCs)逆行标记,用立体定位仪将大鼠固定,根据大鼠双侧上丘和外侧膝状体在颅骨表面的投影,在投影处钻4个骨孔,每孔注入10 g/L的荧光金2μL.2周后采用升高眼压的方法建立大鼠视网膜缺血再灌注模型.将35只SD大鼠随机分为正常对照组(7只),缺血再灌注组(7只)和治疗组(21只).其中治疗组根据再灌注后不同时间予以0.1%Y1231 5μL右眼玻璃体腔注射分为1、3、6 h组,每组7只大鼠.于再灌注后24 h取其视网膜铺片,用荧光显微镜拍照并计算赤道部以内RGCs的数目,对数据进行方差分析.结果 缺血再灌注组与治疗组的RGCs数量均少于正常对照组(P＜0.01).与缺血再灌注组相比,治疗组中1 h和3 h给药组的RGCs数量明显多(P＜0.01),而6 h给药组差异无统计学意义(P=1.0).结论 在视网膜缺血再灌注损伤中,NMDA受体甘氨酸位点拮抗剂Y1231可有效地保护RGCs.     

MSC移植对缺血再灌注损伤视网膜神经节细胞Bcl-2/Bax表达的影响

目的研究骨髓间充质干细胞(mesenchymal stem cells,MSC)移植对视网膜缺血再灌注损伤(retinal ischemia-reperfusion injury,RIRI)视网膜神经节细胞Bcl-2/Bax表达的影响,为MSC移植治疗RIRI提供实验依据。方法 44只SD大鼠分为正常组(4只)、模型组(20只)、MSC移植组(20只)。前房加压法建立大鼠RIRI模型。体外培养大鼠MSC,MSC移植组于再灌注后予以玻璃体腔注射MSC。免疫组织化学法检测各组大鼠视网膜缺血再灌注2h、6h、12h、24h、48h后Bcl-2/Bax表达情况。结果正常组视网膜神经节细胞未见Bcl-2、Bax表达。再灌注后2h、6h、12h、24h、48h,模型组Bcl-2表达分别为0.280±0.008、0.323±0.010、0.474±0.020、0.451±0.011、0.407±0.011,MSC移植组Bcl-2表达分别为0.340±0.006、0.401±0.009、0.610±0.006、0.581±0.009、0.490±0.005;模型组Bax表达分别为0.322±0.007、0.457±0.010、0.469±0.022、0.591±0.014、0.529±0.010,MSC移植组分别为0.252±0.008、0.366±0.011、0.389±0.009、0.433±0.013、0.391±0.004。MSC移植组与模型组比较Bcl-2表达均明显增强(均为P<0.01),Bax表达均明显减弱(均为P<0.01)。结论 RIRI大鼠行MSC移植术,可使神经节细胞Bcl-2表达增强,Bax表达减弱,Bcl-2/Bax比值升高,减少神经节细胞凋亡。MSC移植对RIRI神经节细胞有明显的保护作用。     

Quantity and topography of frog's retinal ganglion cells

Using Rana ridibunda total retinal preparations impregnated with silver, the ganglion cells in central, middle and peripheral retinal zones are counted with the help of a calibrated eyepiece graticule. The percentage of each of the five neuron types (Kalinina, 1974) is found as well as the regularity of their distribution over the retinal zones. The digital data are processed statistically.By calculations the total quantity of the ganglion cells is evaluated as well as the sums of dendrite field areas for the different neuron types. The character of distribution of the different type neuron dendrite fields over the retinal surface is described.The possible functional significance of the established structural properties of ganglion layer cells is discussed.     

经瞳孔温热疗法对急性高眼压大鼠视网膜神经节细胞的保护作用

目的研究低阈值经瞳孔温热疗法（TTT）对急性高眼压大鼠视网膜神经节细胞（RGC）是否具有保护作用。设计实验研究。研究对象BN大鼠。方法采用810nm二极管激光机对10只大鼠视网膜进行热刺激，照射光斑1．2mm，能量50mW，照射时间20s，干预后3d光镜下观察视网膜形态结构的改变，免疫组化方法检测HSP70、HSP27在视网膜组织表达。采用上述激光参数，照射视网膜后3d，制作急性高眼压模型（TTT＋I/R组，n=10），采用TUNEL法检测RGC层细胞凋亡数量，及计数高倍镜下RGC层细胞数，与未干预的急性高眼压模型组（I/R组，n=10）、单纯TTT干预组（TTT组）及正常对照组（n=6）进行比较。主要指标免疫组化染色RGC细胞数及RGC层细胞凋亡数。结果采用低阈值TTT可诱导BN大鼠视网膜神经节细胞HSP70及HSP27表达，且光镜下未出现明显视网膜脉络膜形态的改变。TTT＋I／R组RGC层细胞凋亡数量明显少于I／R组（P=0．048），且前者RGC层细胞数量明显多于后者（辟0．016）；TTT组与正常对照组比较RGC层细胞凋亡数量无显著性差异（P=0．882），但RGC层细胞数明显少于正常对照组（P=0．001）。结论低阈值TTT可诱导BN大鼠视网膜HSP70、HSP27表达，并在急性高眼压损伤下对大鼠RGC凋亡具有抑制作用。（眼科，2007,16：48—51）