视细胞移植后重建视网膜中一氧化氮合酶的分布

近年发现一氧化氮 (ｎｉｔｒｉｃｏｘｉｄｅ ,ＮＯ)是一类新的神经递质 ,在神经系统中起到一种信使作用[1,2 ] 。Ｌ精氨酸在一氧化氮合酶 (ｎｉｔｙｉｃｏｘｄｉｅｓｙｎｔｈａｓｅ ,ＮＯＳ)的催化下分解为Ｌ 瓜氨酸和ＮＯ ,ＮＯ通过提高鸟苷酸环化酶 (ｃＧＭＰ)的水平而发挥生物效应[3] 。在大鼠视网膜内ＮＯＳ主要存在于无长突细胞中[4 ] 。我们通过观察 6 0ｄ的皇家外科学院鼠 (ＲｏｙａｌＣｏｌｌｅｇｅｏｆＳｕｒｇｅｏｕＲａｔ,ＲＣＳ)在接受视细胞移植后重建视网膜中含ＮＯＳ的无长突细胞的变化 ,以及和Ｗｉｓｔａｒ鼠、ＲＣＳ手术对…     

鼠视网膜感光细胞移植术后超微结构观察

目的 以遗传性视细胞变性动物ＲＣＳ鼠为受体,Ｗｉｓｔａｒ鼠为供体,观察纯视锥、杆细胞移植术后ＲＣＳ鼠视网膜外层超微结构的变化。方法 应用视网膜板层切削技术或准分子激光技术制备供体层状视细胞;视网膜板层外路移植技术,获得视网膜移植动物模型。术后２周及４周时处死动物,眼球常规切片后于光镜及透射电镜下观察受体视网膜。结果 移植的视细胞大多成层排列于受体鼠的视网膜色素上皮层及内颗粒层之间。重新出现的外网状     

Wistar鼠和RCS鼠视网膜神经递质的分布和比较

目的：观察正常Wistar大鼠和皇家外科学院鼠（RCS）的视网膜兴奋性神经递质谷氨酸（Glutamate)和抑制性神经递质γ-氨基丁酸（GABA）的分布和两者间的差异。方法：74天Wistar鼠和RCS鼠各6眼分为2组，免疫组织化学染色法，光镜下观察上述组织视网膜内谷氨酸和GABG的分布。结果：Wistar鼠视网膜AGBA阳性免疫反应分布于视网膜内丛状层的部分神经纤维、GABA阳性免疫反应的无长突细胞和节细胞层的部分纤维。RCS鼠则分布于视网膜内丛状层的少量神经纤维、极少量GABA阳性免疫反应的无长突细胞和节细胞层的部分纤维。Wintar鼠视网膜Glutamate阳性免疫反应主要分布于外丛状层、内丛状层及节细胞层的神经纤维。RCS鼠则主要分布于内丛状层及节细胞层的神经纤维。RCS鼠视网膜中Glutamate阳性免疫反应的神经纤维的相对密度和GABA阳性免疫反应的无长突细胞的相对密度减少。结论：74天时RCS鼠视网膜中的视细胞完全萎缩，使Glutamate和GABA的分布受到影响。     

大鼠视网膜一氧化氮合酶神经元分布及缺血性损伤的改变

目的用还原型尼克酰胺腺嘌呤二核苷酸脱氢酶（ＮＡＤＰＨ）－黄递酶（ＮＤＰ）组化染色法研究大鼠视网膜一氧化氮合酶（ｎｉｔｒｉｃｏｘｉｄｅｓｙｎｔｈａｓｅ，ＮＯＳ）神经元的分布及缺血性损伤ＮＯＳ神经元的变化。方法动物模型采用升高眼内压的方法造成视网膜缺血。摘除眼球后，剥离视网膜，进行ＮＡＤＰＨ－ＮＤＰ反应。结果正常大鼠视网膜ＮＯＳ阳性神经元仅分布于内核层内侧，呈散在分布，具有较长的串株样突起。视网膜缺血１０、３０、６０ｍｉｎ组ＮＯＳ阳性神经元同对照组相比形态学改变及计数均无显著性差异（Ｐ＞０．０５）；而缺血９０ｍｉｎ组，ＮＯＳ阳性神经元数量减少，与对照组相比有显著性差异（Ｐ＜０．０５）。结论正常大鼠视网膜ＮＯＳ阳性神经元散在分布于内核层内侧，可能是无长突细胞；视网膜缺血早期ＮＯＳ阳性神经元无明显变化，提示一氧化氮（ＮＯ）可能不介导ＮＭＤＡ受体激活所致的细胞毒性，缺血晚期数量减少则可能由于ＮＯＳ阳性神经元死亡。     

鼠光感受器细胞层移植的方法及观察

目的 研究视锥和视杆细胞与周围组织间在解剖结构及是生理等方面的关系。方法 取２０只同龄Ｗｉｓｔａｒ和ＲＣＳ鼠作为供体和受体,利用视见解发削技术取得视锥及视杆细胞层,并植入ＲＣＳ鼠眼视网膜下。术后２周时摘除术眼,于光镜下观察交摄影。结果 术后２周,在视网膜完全复位的受体眼,移植的纯视锥和视杆细胞成活,可见移植细胞位于网膜下腔的视网膜色素上皮（ｒｅｔｉｎａｌ ｐｉｇｍｅｎｔ ｅｐｉｔｈｅｌｉｕｍ,ＲＰ     

糖尿病早期大鼠视网膜微血管改变的形态学研究

目的研究糖尿病早期大鼠视网膜微循环的形态学改变及白细胞在糖尿病视网膜病变（ｄｉａ－ｂｅｔｉｃｒｅｔｉｎｏｐａｔｈｙ，ＤＲ）微循环障碍中的作用。方法雄性成年Ｗｉｓｔａｒ大鼠１２只，随机分为正常对照组、链脲佐菌素（ｓｔｒｅｐｔｏｚｏｔｏｃｉｎ，ＳＴＺ）糖尿病大鼠３、６个月组各４只。动物活体灌注固定，视网膜消化铺片，光镜观察，计数周细胞并行统计分析。结果糖尿病大鼠６个月组视网膜毛细血管周细胞数明显减少，并见毛细血管有白细胞栓塞。结论大鼠注射ＳＴＺ后６个月出现ＤＲ的早期改变，白细胞栓塞毛细血管形成ＤＲ微循环障碍。     

荧光金逆行标记大鼠视网膜节细胞

视网膜节细胞（ｒｅｔｉｎａｌｇａｎｇｌｉｏｎｃｅｌｌｓ，ＲＧＣ）的准确计数是研究正常及病理状态下ＲＧＣ分布和死亡的关键指标。传统的Ｎｉｓｓｅｌ法等组织化学技术无法将ＲＧＣ与视网膜内其它神经元彻底区分，尤其是与“移位”的无长突细胞鉴别。我们将荧光金（ｆｌｕｒｏｇｏｌｄ，ＦＧ）注射于ＳＤ大鼠ＲＧＣ的主要靶核团［１］，观察投射于这些核团的ＲＧＣ能否被ＦＧ逆行标记，荧光染料能否在ＲＧＣ胞体中长期存留，以及成年ＳＤ大鼠ＲＧＣ的数目及分布。１　材料与方法１１　试剂与实验动物　ＦＧ购自Ｆｌｕｒｏｃｈｒｏｍｅ…     

视网膜神经节细胞体外培养、纯化及生物学特性研究

目的 建立体外视网膜神经节细胞（ｒｅｔｉｎａｌｇａｎｇｌｉｎｃｅｌｌｓ,ＲＧＣｓ）培养和纯化模型。方法 出生后１－３天Ｓｐｒａｇｕｅ－Ｄａｗｌｅｙ（ＳＤ）乳鼠,ＲＧＣｓ在ｂａｓａｌｍｅｄｉｕｍｅａｇｌｅ（ＢＭＥ）培养基中培养,相差显微镜下观察细胞生长规律。羊抗鼠单克隆抗体ＦＩＴＣ－Ｔｈｙ－１,１鉴定ＲＧＣｓ并通过Ｔｈｙ１．１单抗进行ＲＧＣｓ的分离纯化,四唑盐（ｍｏｎｏｔｅｔｒａｚｏｌｉｕｍ,ＭＴＴ     

大鼠视网膜神经细胞的培养

建立视网膜神经节细胞（ｒｅｔｉｎａｌｇａｎｇｌｉｏｎｃｅｌｌｓ,ＲＧＣｓ）的体外培养方法,为ＲＧＣｓ的体外实验研究奠定基础。方法采用胰酶消化将１６只生后２－３天的Ｓｐａｇｕｅ－Ｄａｗｌｅｙ大鼠视网膜制成细胞悬液后,接种于涂以鼠尾胶原的２４孔培养板,预先置入１ｃｍ＊１ｃｍ的载玻片。     

视网膜下腔接种视网膜S抗原诱导的免疫偏离

目的 确立视网膜下腔是否具有支持针对视网膜可溶性抗原（Ｓ抗原）刺激诱导偏离式免疫反就原能力，并观察白细胞介素－１（ＩＬ－１）对视网膜下腔免疫特性的影响。方法 将视网膜Ｓ抗原接种于Ｗｉｓｔａｒ大鼠的眼前房和视网膜下腔。抗原接种后７天，使用Ｓ原接种于Ｗｉｓｔａｒ大鼠的眼前房和视风膜下腔。抗原接种后７天，使用Ｓ抗原和完全福氏佐免疫受主动物。然后，通过足部刺激评估迟发型超敏反应（ＤＴＨ）。通过腹腔注射ＩＬ     

一氧化氮与眼病的关系

一氧化氮（nitric oxide,NO）是近年来眼科疾病的研究热点.其在体内一氧化氮合酶（nitric oxide synthase,NOS）的催化下生成,作为一种小分子介质调节眼部血流.诸多脉络膜视网膜疾病如葡萄膜炎、青光眼、缺血-再灌注损伤、前部缺血性视神经病变、糖尿病视网膜病变以及视网膜色素变性等发病机制中均发现NO的异常,与NO相拮抗的内皮素-1（Endothelin-1,ET-1）也日益受到关注.对NO合成途径的干预有望成为一种新的眼科治疗手段.     

氧化应力对晶状体一氧化氮和一氧化氮合酶活性的影响

探讨氧化应力、５种抗白内障药物对晶状体一氧化氮合酶（ＮＯＳ）活性及一氧化氮（ＮＯ）水平的影响,方法建立晶状体温育模型：培养液分７组：（１）对照组含ＤＭＥＭ １０ｍｌ;（２）－（７）ｘｅｇ ｗｙｎｋＤＭＥＭ１０ｍｌ外尚有３０％Ｈ２Ｏ２０．２ｍｌ,ＦｅＣＬ３２ｍｇ并于（３）－（７）组中分别加入海珠视、麝珠明目、益视安、晶福及视明露滴眼液各１．０ｍｌ,晶状体制备均浆上清,测ＮＯＳ,ＮＯ,ＭＤＡ。结果１．     

一氧化氮合成酶在正常幼猫视觉系统的分布

目的 观察一氧化氮合成酶在正常幼猫视觉系统的分布,探讨一氧化氮在视觉系统中的作用。方法 用ＮＡＤＰＨ黄递酶（ＮＤＰ）组织化学染色法观察了一氧化氮合成酶在正常幼猫视觉系统视网膜、外侧膝状体、视皮 分布、结果 正常幼猫视网膜和视皮层１７区均可见ＮＯＳ阳性细胞和纤维;外太体（ＬＧＮ）各层无ＮＯＳ阳性细胞,但可见ＮＯＳＢ是性纤维,结论一氧化氮可能作为一种重要的神经递质参与视觉信息的形成、整合传递     

Effects of inhibition of neuronal nitric oxide synthase on basal retinal blood flow regulation

Nitric oxide (NO) has been observed to regulate blood flow under basal and stimulated conditions in the retina. Recent evidence suggests that NO produced by neuronal nitric oxide synthase (nNOS) may regulate blood flow in addition to that produced by endothelial nitric oxide synthase (eNOS). The objective of the current study was to investigate the contribution of NO produced by nNOS in the regulation of basal retinal blood flow. A non-specific NOS inhibitor N (G)-nitro-l-arginine methyl ester (l-NAME) and the specific nNOS inhibitors 1-(2-trifluoromethylphenyl) imidazole (TRIM) and (4S)-N-(4-amino-5 [aminoethyl] aminopentyl)-N-nitroguanidine (AAAN) were injected into the vitreous (intravitreal) of Long-Evans rats. Vessel diameters, velocities and volumetric blood flow rates (VBF) in the retinal circulation were determined prior to and in 30-min intervals for 4-4.5 h after injection. In addition, the basal amount of nNOS in the rat retina was quantified using a specific enzyme linked immunoassay (ELISA). Treatment with l-NAME and TRIM significantly decreased diameters and VBF. Compared with saline, treatment with l-NAME and TRIM produced a significant (p < 0.001) decrease of ∼12-17% in vessel diameters. Treatment with AAAN significantly decreased vessel diameters and venous VBF. Compared with saline AAAN produced a significant decrease of ∼7% in arterial (p < 0.001) and 5% in venous (p = 0.011) diameters, respectively. The amount of nNOS in the rat retina was 0.17 ± 0.0147 pmol mg⁻¹ of dry retina. The results suggest that though inhibition of nNOS decreases basal diameters, constant VBF is maintained in the retinal circulation.     

一氧化氮和一氧化氮合酶基因多态性与糖尿病视网膜病变

糖尿病视网膜病变(diabetic retinopathy,DR)是重要致盲性眼病之一,其发生和进展与血糖水平、疾病病程、环境及遗传等多种因素有关。一氧化氮(NO)作为一种重要的血管活性物质,与DR中毛细血管闭塞、微循环障碍、内皮细胞增殖相关。一氧化氮合成酶(NOS)是NO合成过程中的关键酶,我们就NO和NOS基因多态性与DR的关系进行综述。     

Inhibition of nitric oxide synthesis in corneas in storage media

The nitrate/nitrite content in storage media was determined after nitric oxide synthase inhibition by adding 400 microl of 100 mm N(G)-monomethyl-l-arginine (LMMA) to four chambers of Optisol GS corneal storage media, each containing one viable human cornea. The companion corneas in storage media without LMMA served as controls. Four hundred microlitre aliquots obtained at baseline (day 0) and at one-day intervals for 20 more days for both groups were analyzed for nitrate and nitrite (breakdown products of nitric oxide) concentration levels using a spectrophotometric method based on the Greiss reaction. Average nitrate/nitrite concentrations, statistically analyzed using a polynomial random coefficients model, showed a statistically significant marked reduction in the levels of nitrate and nitrite accumulation in the study chambers as compared to control chambers for days 1-20(P < 0.001) There was also a reduction in the accumulation rate of nitrate and nitrite concentrations, as compared to controls (P < 0.05) until around day 8 when the differences in rates were no longer statistically significant. The progressive increase in nitrate and nitrite accumulation in corneal storage media can be blunted by the addition of a nitric oxide synthase inhibitor. Given the toxic free radical properties of nitric oxide, corneas in storage awaiting transplantation may benefit from having a nitric oxide synthase inhibitor added to storage media.     

一氧化氮与血管生成的研究进展

一氧化氮(NO)是一种重要的信使分子和生物活性物质,参与调节机体的一系列生理活动以及新生血管生成等病理过程.本文就NO及其合成酶(NOS)在血管生成中的作用做一简要综述.     

Nitric oxide and cyclic guanosine monophosphate signaling in the eye

This brief review describes the components and pathways utilized in nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) signaling. Since the discovery of the effects of NO and cGMP on smooth muscle relaxation about 30 years ago, the field has expanded in many directions such that many, but not all, biochemical and biological effects seem to be regulated by these unique signaling molecules. While many of the effects of NO are due to activation of soluble guanylyl cyclase (sGC) that can be considered the receptor for NO, cGMP, in turn, can activate a cGMP-dependent protein kinase (PKG) to phosphorylate an array of proteins. Some of the effects of cGMP can be independent of PKG and are due to effects on ion channels or cyclic nucleotide phosphodiesterases. Also, some of the effects of NO can be independent of sGC activation. The isoenzymes and macromolecules that participate in these signaling pathways can serve as molecular targets to identify compounds that increase or decrease their activation and thus serve as chemical leads for discovering novel drugs for a variety of diseases. Some examples are given. However, with about 90,000 publications in the field since our first reports in 1977, this brief review can only give the readers a sample of the excitement and opportunities we have found in this cell signaling system.     

一氧化氮与葡萄膜炎

一氧化氮（ｎｉｔｒｉｃｏｘｉｄｅ，ＮＯ）是新近被鉴定为具有多种生物活性效应的气体分子，对多种病原菌、肿瘤细胞及某些正常细胞具有毒性作用。简介一氧化氮一般情况及其在葡萄膜炎中的病理效应，并探讨调节其效应作为治疗人类葡萄膜炎的新途径。