Triamcinolone Acetonide Prevents Enhancement of Hypoxia-induced Neuronal and Inducible Nitric Oxide Synthases in the Retinas of Rats with Oxygen-induced Retinopathy

Purpose

We investigated whether oxygen-induced retinopathy (OIR) results in changes in the protein expression of neuronal and inducible nitric oxide synthases (nNOS and iNOS, respectively) in rat model of OIR. In addition, we evaluated whether treatment of rats with triamcinolone acetonide (TA) prevents this response.

Methods

To promote OIR, Sprague-Dawley rats were exposed to hyperoxia from postnatal day 2 (P2) to P14. They were then returned to normoxia after P15. TA was injected into the right vitreous of P15 rats, while saline was injected into the left vitreous. At P18 the expression of nNOS and iNOS was determined using Western blotting and immunostaining techniques in retinas obtained from control rats.

Results

In P18 OIR rats, the abundance of nNOS and iNOS protein was significantly increased compared with controls. These increases were not observed in the retinas of rats treated with TA. The change in expression of nNOS and iNOS were specific to parvalbumin and glial fibrillary acidic protein-positive cells. Treatment with TA prevented the increased expression of nNOS and iNOS in all samples.

Conclusions

Hypoxia upregulates expression of nNOS and iNOS in OIR rat retinas, which is can be prevented by treatment with TA.     

Triamcinolone reduces neovascularization, capillary density and IGF-1 receptor phosphorylation in a model of oxygen-induced retinopathy

PURPOSE: To study the effects of intravitreous triamcinolone acetonide (TA) on neovascularization (NV), capillary density, and retinal endothelial cell (REC) viability in a model of oxygen-induced retinopathy (OIR). METHODS: Newborn rats exposed to OIR underwent intravitreous injections (right eye) at day 14 to achieve intravitreous concentrations of: dexamethasone (DEX) (0.3 mg/mL), triamcinolone (TA; 0.4-4 mg/mL), or PBS. Animals were removed to room air and at day 18, retinal flatmounts were assayed for clock hours of NV, percent peripheral avascular retina, capillary density, apoptosis, and VEGF protein. At day 15, retinas were assayed for insulin-like growth factor (IGF)-1 receptor phosphorylation (IGF-1Rphos). Human RECs exposed to TA were assayed for trypan blue exclusion or activated caspase-3. RESULTS: TA but not DEX or PBS reduced NV (ANOVA, P < 0.001), capillary density (ANOVA, P < 0.001), and systemic weight gain (ANOVA, P = 0.002). VEGF protein was not different between TA- and PBS-injected or noninjected groups. Apoptosis was not increased in vivo or in vitro between groups, but there was a dose-dependent toxic effect of TA on cultured RECs (P < 0.001). At day 15, retinas from the 4 mg/mL TA-injected OIR group had a trend toward reduced IGF-1Rphos compared with room air-raised PBS- or non-injected OIR groups. CONCLUSIONS: TA caused dose-dependent reductions in NV, retinal vascularization, and systemic weight gain associated with a reduction in IGF-1Rphos. Long-term studies are needed to assess TA toxicity in vivo. TA doses should be carefully considered before administering the drug in diseases with ongoing retinal vascular development, such as retinopathy of prematurity.     

Role of unc5b in retinal neovascularization in mice with oxygen-induced retinopathy

AIM: To explore the role of unc5b in retinal neovascularization in murine oxygen-induced retinopathy (OIR). METHODS: On postnatal 7(P7), C57BL/6J mice were exposed to 75%±2% oxygen for 5 days. On postnatal 12(P12), the mice were brought back to the room air (21% oxygen) to induce retinal neovascularization. Western blot analysis was performed to examine the temporal expression of unc5b in murine retinas. Double staining for unc5b and isolectin B4 were employed to determine the location of unc5b in murine retinas. The effect of unc5b on retinal neovascularization was evaluated by intravitreal injection of unc5b-FC in mice with OIR. Retinal neovascularization was measured by counting neovascular cell nuclei above the internal limiting membrane and by angiography of flat-mounted retinas perfused with fluorescein dextran. RESULTS: Compared to age-matched normal mice, the expression of unc5b was significantly increased in retinas of OIR mice on P17 and P21. Unc5b was apparently expressed in retinal vessels of OIR while being negative in normal retinal vessels. Retinal neovascularization in eyes injected with unc5b-FC was significantly reduced. CONCLUSION: Unc5b-FC can effectively inhibit retinal neovascularization induced by OIR. It may serve as a powerful and novel therapy for ischemia-induced retinal disease.     

Purinergic receptor activation inhibits osmotic glial cell swelling in the diabetic rat retina

The anti-inflammatory glucocorticoid, triamcinolone acetonide, is used clinically for the rapid resolution of diabetic macular edema. Osmotic swelling of glial cells may contribute to the development of retinal edema. Triamcinolone inhibits the swelling of retinal glial cells of diabetic rats. Here, we determined whether the effect of triamcinolone is mediated by a receptor-dependent mechanism. Hyperglycemia was induced in rats with streptozotocin injection. After 6-10 months, the swelling properties of glial cells in retinal slices upon hypotonic challenge were determined. Nucleotide-degrading ecto-enzymes were immunostained in retinal slices and glial cells. Hypotonic challenge did not change the size of glial cell bodies from control retinas but induced swelling of cells from diabetic animals. Triamcinolone inhibited glial cell swelling; this effect was prevented by a selective antagonist of adenosine A1 receptors, an inhibitor of nucleoside transporters, inhibitors of adenylyl cyclase and protein kinase A activation, and inhibitors of potassium and chloride channels. In diabetic (but not control) retinas, the effect of triamcinolone apparently involves extracellular nucleotide degradation. Glial cells from diabetic retinas displayed immunolabeling against nucleoside triphosphate diphosphohydrolase-1 (NTPDase1) which was not observed in control retinas. The mRNA expression for NTPDase1 was significantly increased in the retina of diabetic rats. It is suggested that triamcinolone induces the release and formation of endogenous adenosine that subsequently activates A1 receptors resulting in ion efflux through potassium and chloride channels and prevention of osmotic swelling. Whereas adenosine is liberated via facilitated transport in control retinas, an extracellular formation of adenosine contributes to the effect of triamcinolone in diabetic retinas.     

脂多糖诱导炎症对大鼠氧诱导视网膜病变的影响

目的　观察不同剂量脂多糖（ｌｉｐｏｐｏｌｙｓａｃｃｈａｒｉｄｅ,ＬＰＳ）诱导炎症对大鼠氧诱导视网膜病变（ｏｘｙｇｅｎ-ｉｎｄｕｃｅｄｒｅｔｉｎｏｐａｔｈｙ,ＯＩＲ）的影响,以探讨炎症在早产儿视网膜病变（ｒｅｔｉ-ｎｏｐａｔｈｙｏｆｐｒｅｍａｔｕｒｉｔｙ,ＲＯＰ）中的作用。方法　将新生ＳＤ大鼠随机分组,实验组依据ＬＰＳ注射剂量的不同分为ＬＰＳ-５０、ＬＰＳ-１００和ＬＰＳ-５００组,并分别设立正常对照组（Ｎ组）和氧诱导对照组（ＯＩＲ组）。Ｎ组幼鼠喂养于空气中,实验组和ＯＩＲ组幼鼠饲养于氧气体积分数为８０％／２１％（２４ｈ交替一次）的氧箱中至出生后１４ｄ（Ｐ１４）,随后移至空气中继续饲养。实验组幼鼠行ＯＩＲ处理过程中,于Ｐ７行ＬＰＳ腹腔注射,ＬＰＳ-５０、ＬＰＳ-１００和ＬＰＳ-５００组注射剂量分别为５０μｇ?ｋｇ－１、１００μｇ?ｋｇ－１和５００μｇ?ｋｇ－１。检测各组幼鼠在Ｐ７（注射前）、Ｐ８、Ｐ１１和Ｐ１４等不同时间点的体质量变化;并分别于Ｐ１４和Ｐ１８制作全视网膜铺片,通过ＧＳ-ｉｓｏｌｅｃｔｉｎＢ４染色观察各组视网膜血管化及病理性新生血管情况。结果　在各检测时间点,各实验组和ＯＩＲ组幼鼠的体质量均低于Ｎ组（Ｐ＜０．０５）。Ｐ７时,各实验组和ＯＩＲ组体质量无差别（Ｐ＞０．０５）;至Ｐ８、Ｐ１１和Ｐ１４时,ＬＰＳ-５００组幼鼠体质量明显低于ＯＩＲ组和其他实验组（Ｐ＜０．０５）。Ｐ１４时,Ｎ组幼鼠的浅层视网膜血管已覆盖整个视网膜;而ＯＩＲ组和实验组幼鼠的视网膜均存在无血管区,且ＬＰＳ-５００组无血管区面积最大（２７．３２％ ±３．５８％,Ｐ＜０．０１）。Ｐ１８时,Ｎ组视网膜血管网层次结构清晰;ＯＩＲ组和实验组幼鼠的视网膜均出现病理性新生血管,且ＬＰＳ-５００组新生血管累及视网膜的范围最广（累及钟点数为６．８３±１.７２,Ｐ＜０．０１）。结论　ＬＰＳ诱导炎症可加重大鼠ＯＩＲ,且在一定范围内呈剂量依赖性,提示炎症可能参与ＲＯＰ病理过程。     

New quantitative analysis, using high-resolution images, of oxygen-induced retinal neovascularization in mice

Oxygen-induced retinopathy (OIR) has been widely studied as an animal model of retinal neovascularization diseases. Evaluation using this model is mainly performed by counting cell nuclei above the internal limiting membrane in serial cross-sections or by scoring in flat-mounted retinas. Quantitative evaluation is important for accurate elucidation of pathological conditions and the drug evaluations. We therefore attempted quantification using new imaging software and high-resolution images taken with a high-resolution CCD camera. Neonatal mice were exposed to 75% oxygen from postnatal day 7 (P7) to P12, then returned to room air until P17. At each evaluation time, mice were perfused with fluorescein-dextran, and flat-mounted retinas were prepared. Total images of the retinal vasculature were collected and analyzed using the imaging software. P17 normal retinas showed increases in computerized total tube area, total tube length, number of segments, and number of branch points (versus P7 normal retinas). These increases coincided with the development of the retinal vasculature between P7 and P17. P17 OIR retinas similarly showed increases in those parameters, and the number of nodes (thick regions exceeding the maximum width of the vessel) and the node area (abnormality induced by OIR) were markedly increased (versus P17 normal retinas). Accordingly, this approach is considered most suitable for evaluating the number of nodes and node area in this model. Quantification using the present imaging software should be useful for evaluating physiological and pathological neovascularizations in this OIR model.     

Activated NAD(P)H oxidase from supplemental oxygen induces neovascularization independent of VEGF in retinopathy of prematurity model

PURPOSE: To study NAD(P)H oxidase-dependent outcomes after oxygen stresses that are similar to those experienced by preterm infants today using a rat model of retinopathy of prematurity. METHODS: Within 4 hours of birth, pups and their mothers were cycled between 50% and 10% oxygen daily for 14 days and were returned to room air (21% O2, 50/10 oxygen-induced retinopathy [OIR]) or supplemental oxygen (28% O2, 50/10 OIR+SO) for 4 days. Pups received intraperitoneal injections of the specific NAD(P)H oxidase inhibitor apocynin (10 mg/kg/d) or of PBS from postnatal day (P)12 to P17, and some received intraperitoneal injections of hypoxyprobe before kill. Intravitreous neovascularization (IVNV), avascular/total retinal areas, vascular endothelial growth factor (VEGF), NAD(P)H oxidase activity, or hypoxic retina (conjugated hypoxyprobe) were determined in neurosensory retinas. Human retinal microvascular endothelial cells (RMVECs) treated with apocynin or control were exposed to 1% or 21% O2 and assayed for phosphorylated (p-)Janus kinase (JNK) and NAD(P)H oxidase activity. RESULTS: Retinas from 50/10 OIR+SO had increased NAD(P)H oxidase activity and lower VEGF than did retinas from 50/10 OIR. Apocynin treatment reduced the IVNV area and hypoxic retina in 50/10 OIR+SO. RMVECs treated with 1% O2 had increased p-JNK compared with RMVECs exposed to room air. CONCLUSIONS: Different oxygen stresses activate NAD(P)H oxidase to varying degrees to trigger disparate pathways (angiogenesis or apoptosis). The oxygen stresses and outcomes used in this study are relevant to human ROP and may explain some of the complexity in the pathophysiology of ROP resulting from oxygen exposure.     

CCR7/p-ERK1/2/VEGF signaling promotes retinal neovascularization in a mouse model of oxygen-induced retinopathy

AIM: To investigate the role of CCR7/p-ERK1/2/VEGF signaling in the mouse model of oxygen-induced retinopathy (OIR). METHODS: Neonatal C57BL/6J mice were evenly randomized into four groups: normoxia, OIR, OIR control (treated with scramble siRNA), and OIR treated (treated with CCR7 siRNA). Normoxia group was not specially handled. Postnatal day 7 (P7) mice in the OIR group were exposed to 75%±5% oxygen for 5d (P7-P12) and then maintained under normoxic conditions for 5d (P12-P17). Mice in the OIR control and OIR treated groups were given injections of scramble or CCR7 siRNA plasmid on P12 before returning to normoxic conditions for 5d (P12-P17). Retina samples were collected from all mice on P17, stained with adenosine diphosphatase (ADPase), and retinal neovascularization (RNV) was assessed. Retinas were also stained with hematoxylin and eosin (H&E) for RNV quantitation. The distribution and expression of CCR7, p-ERK1/2 and vascular endothelial growth factor (VEGF) were assessed via immunohistochemistry, Western blot, and quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: High oxygen promoted retinal neovascularization (P<0.05) and increased the number of endothelial nuclei in new vessels extending from the retina to the vitreous body; CCR7 promoted this process (P<0.05). CCR7 and VEGF mRNA were expressed at higher levels in the OIR and OIR control groups than in the normoxia and OIR treated groups. CCR7, p-ERK1/2, and VEGF protein were expressed in the retinas of mice in the OIR and OIR control groups. Intravitreal injection of CCR7 siRNA significantly reduced CCR7, p-ERK1/2, and VEGF expression in the OIR mouse model (all P<0.05). CCR7 significantly enhanced the neovascularization and non-perfusion areas in the OIR group (P<0.05). CCR7 siRNA significantly reduced levels of p-ERK1/2 and VEGF as compared to OIR controls (P<0.05). CONCLUSION: These results suggest that CCR7/p-ERK 1/2/VEGF signaling plays an important role in OIR. CCR7 may be a potential target for the prevention and treatment of retinopathy of prematurity.     

甲酰肽受体Fpr2在氧诱导视网膜病变小鼠新生血管形成中的作用及相关机制研究

目的　探讨甲酰肽受体Fpr2在氧诱导视网膜病变（OIR）小鼠中对胶质细胞改变的影响,并探讨其在新生血管形成中的作用及机制。方法　将新生C57BL/6J小鼠、Fpr2^-/-小鼠分别诱导建立OIR模型后分为氧诱导组和Fpr2^-/-氧诱导组。正常对照组和Fpr2^-/-组小鼠正常环境饲养。收集各组小鼠视网膜组织并制作成冰冻切片,免疫荧光染色观察小鼠视网膜中波形蛋白（Vimentin）、神经胶质纤维酸性蛋白（GFAP）和离子化钙结合适配分子1(IBA1)变化;实时荧光定量PCR(RT-PCR)检测小鼠视网膜中炎症因子mRNA的表达;Western blot检测小鼠视网膜中细胞外调节蛋白激酶(ERK)和P38的蛋白磷酸化表达。免疫荧光染色法观察小鼠视网膜中新生血管和无灌注区情况。结果　免疫荧光染色结果显示,与正常对照组相比,氧诱导组和Fpr2^-/-氧诱导组小鼠视网膜中Vimentin、GFAP、IBA1表达均明显增加,而与氧诱导组相比,Fpr2^-/-氧诱导组小鼠视网膜中Vimentin、GFAP、IBA1表达均降低(均为P<0.05)。RT-PCR检测结果显示,与Fpr2^-/-氧诱导组相比,氧诱导组小鼠视网膜中白细胞介素-1β (IL-1β)、肿瘤坏死因子-α (TNF-α)、白细胞介素-6(IL-6) mRNA相对表达量均增加(均为P<0.05)。Western blot检测结果显示,与正常对照组相比,氧诱导组和Fpr2^-/-氧诱导组小鼠视网膜中p-ERK 1/2和p-P38蛋白相对表达量均增加,而与氧诱导组相比,Fpr2^-/-氧诱导组小鼠视网膜中p-ERK 1/2和p-P38蛋白相对表达量均减少(均为P<0.05)。与氧诱导组相比,Fpr2^-/-氧诱导组小鼠视网膜中新生血管形成和无灌注区面积均减少（均为P<0.05）。结论　抑制Fpr2能够抑制OIR模型小鼠视网膜胶质细胞活化,下调炎症因子表达,减少视网膜新生血管形成和无灌注区面积,此过程中涉及ERK、P38信号通路的作用。     

塞来昔布对糖尿病大鼠视网膜缝隙连接蛋白Cx43的作用

目的：观察COX-2(cyclooxygenase,COX-2)抑制剂(塞来昔布)对糖尿病大鼠视网膜缝隙连接蛋白Cx43(connexin43, Cx43)表达的影响。

方法：选取SD(Sprague-Dawley)大鼠45只,随机分为3组：对照组、糖尿病组、用药组,每组各15只,采用STZ腹腔注射造模的方式进行造模,快速血糖仪监测各组大鼠空腹血糖,正常对照组、糖尿病模型组、用药组分别用生理盐水、生理盐水、塞来昔布溶液进行灌胃,3mo后采用过量麻醉法处死大鼠,制备视网膜标本,采用免疫组化法观察Cx43蛋白,实时定量PCR技术检测大鼠视网膜Cx43 mRNA的相对表达量,采用SPSS13.0统计软件进行统计分析,对各组检测结果进行比较。

结果：免疫组织化学染色缝隙连接蛋白Cx43在视网膜大鼠的神经节细胞层、神经纤维层、内丛状层、色素上皮层、内皮细胞层可见表达不同程度点状、片状表达,计算机图像灰度分析发现塞来昔布对糖尿病大鼠视网膜Cx43表达有促进作用,正常对照组、糖尿病组、用药组灰度值分别是0.233±0.025、0.124±0.014、0.197±0.021,两两比较差异均有统计学意义(P<0.05); 实时定量PCR检测发现塞来昔布促进糖尿病大鼠Cx43 mRNA表达量增加,正常对照组、糖尿病组、用药组相对表达量分别是0.635±0.084、0.110±0.061、0.367±0.074,两两比较差异有统计学意义(P<0.05)。

结论：缝隙连接蛋白Cx43在糖尿病大鼠视网膜中表达减少,塞来昔布可以减缓糖尿病大鼠视网膜缝隙连接蛋白Cx43表达的减少。     

Differential gene expression pattern of diabetic rat retinas after intravitreal injection of erythropoietin

Background: To profile the pattern of gene expression in diabetic rat retinas with or without intravitreal injection of erythropoietin. Design: By using streptozotocin‐induced diabetic rats, after intravitreal injection of erythropoietin, neurosensory retinas were collected to determine the effect of erythropoietin on gene expression. Participants: Three groups of Sprague–Dawley rats were studied: normal control (15), diabetic rats with saline injection (15) and diabetic rats with intravitreal erythropoietin treatment (15). Methods: Diabetes was induced by intra‐peritoneal injection of streptozotocin. Intravitreal injection of erythropoietin was performed at the following time points: 0, 30 and 120 days after diabetes onset. Four days after each injection at above‐mentioned time points, the retinas were harvested for microarray assay. The real‐time PCR was used to evaluate the microarray data. Results: Genes encoding inflammatory factors, such as interleukin‐2 and interleukin‐11, which were upregulated in the diabetic retinas, were restored after erythropoietin treatment. Genes encoding pro‐apoptotic effectors, like Tnfrsf5, Bid3 and Bcl2l1, were also upregulated in diabetic rats and attenuated in erythropoietin‐treated group. In addition, real‐time PCR were employed to confirm the changes of the genes Trex2, G1P2, DHX58, RGD1311906 and LOC689064, which have not been reported in diabetic retinopathy. Conclusions: Intravitreal erythropoietin treatment is able to normalize the gene expression responsible for pro‐apoptotic and inflammatory responses noted in diabetic retinas.     

精氨酸-谷氨酰胺在幼鼠早产儿视网膜病变模型中的应用(英文)

目的:观察精氨酸-谷氨酰胺(Arg-Gln)对早产儿视网膜病变动物模型视网膜新生血管的抑制作用。方法:48只7日龄的C57BL/6J新生鼠暴露在750mL/L高氧环境中5d,然后回到正常空气中建立早产儿视网膜病变的动物模型。在鼠龄12d时实验组(36只)新生鼠每天两次腹腔注射Arg-Gln(剂量分别为1.0,3.0,5.0g/kg,每组12只),连续注射5d;对照组(12只)每天两次腹腔注射PBS,连续5d。所有小鼠均于17d处死,视网膜铺片,ADP酶染色观察视网膜血管情况。HE染色,在光学显微镜下观察并计数突破视网膜内界膜的血管内皮细胞细胞核数目。Real-time RT-PCR方法测量每组视网膜VEGF mRNA水平。结果:与对照组相比,实验组以剂量依赖方式无灌注区面积和新生血管团逐渐减少;实验组中最大剂量组[5.0g/(kg·d)]突破内界膜的内皮细胞细胞核数目比对照组大约减少75%(P<0.01);实验组视网膜VEGF mRNA水平与对照组相比明显下降。结论:Arg-Gln能够有效抑制早产儿视网膜病变动物模型视网膜新生血管的生成,可能为临床提供一种预防和治疗早产儿视网膜病变安全有效的新方法。     

玻璃体腔注射VAS2870对小鼠氧诱导视网膜病变的保护作用

目的：观察玻璃体腔注射VAS2870对C57小鼠氧诱导视网膜病变的影响。方法：将新生C57 BL/6 J小鼠随机分为3组,分别为正常对照组、VAS2870注射 OIR 组和无菌 PBS 缓冲液注射OIR组。将后两组小鼠在出生后第7 d ( P7)至P12置于体积分数为75%±2%的恒定高氧氧箱中以构建OIR模型,在 P12时给予幼鼠双眼玻璃体腔注射 VAS2870(0.5μL),另一组幼鼠双眼注射同等剂量的无菌PBS缓冲液。三组小鼠均在 P17时取右眼行视网膜铺片和Lectin染色,观察视网膜中央无血管区及病理性新生血管的情况;取右眼行视网膜组织定量检测 ROS/RNS 含量;取左眼应用RT-PCR检测Nox4 mRNA含量,并应用Western-blot测定视网膜组织中VEGF的表达。结果：VAS2870注射OIR组小鼠视网膜中央无血管区面积较无菌PBS缓冲液注射OIR组明显减少( P<0.05),病理性新生血管数目明显减少( P<0.05);VAS2870注射OIR组小鼠视网膜组织Nox4 mRNA的表达量明显低于无菌PBS缓冲液注射组;VAS2870注射OIR组小鼠视网膜组织ROS含量较无菌PBS缓冲液注射组明显降低( P<0.05);VAS2870注射OIR组小鼠视网膜组织VEGF的表达明显低于无菌PBS缓冲液注射组( P<0.05)。结论：在小鼠OIR模型中, VAS2870可抑制Nox4 mRNA的表达,减少ROS/RNS,下调VEGF的生成,在视网膜病变进程中具有保护作用。     

玻璃体腔注射塞来昔布抑制大鼠视网膜新生血管的作用

目的:通过对大鼠氧诱导视网膜病变(oxygen-induced retinopathy,OIR)模型进行玻璃体腔注射塞来昔布,探讨塞来昔布在OIR中对视网膜新生血管的作用及其机制.方法:选取7天龄SD乳鼠96只随机分为6组:Z组:正常组;O组:OIR组;A组:OIR+溶媒对照组;B组:OIR+塞来昔布5μg组;C组:OIR+塞来昔布20μg组;D组:OIR+塞来昔布80μg组.除Z组在正常环境饲养外,其余各组乳鼠均建立OIR模型.乳鼠于生后第12 d出氧箱后给予玻璃体内注射二甲基亚砜(dimethyl sulfoxide,DMSO)及相应剂量的塞来昔布,于生后第17 d处死,做组织切片HE染色观察视网膜组织形态并计数突破内界膜的血管内皮细胞核数,石蜡切片行免疫组化染色检测VEGF蛋白的表达.结果:HE染色显示,Z组、O组、A组、B组、C组、D组突破视网膜内界膜的血管内皮细胞核数分别为0.44±0.18、30.60±5.36、28.05±4.68、19.58±4.58、10.13±1.93、7.58±2.68个;除O组与A组外,各组间差异均有统计学意义(P<0.05),经塞来昔布治疗后,突破内界膜的血管内皮细胞核明显减少,且与剂量正相关;免疫组化结果显示,Z组VEGF蛋白表达呈阴性,表达率为10%,其余各组可见VEGF蛋白的阳性表达,O、A组阳性表达较高,阳性率分别为90%、86%,表现为棕褐色颗粒或团块,均高于B、C、D组,且三组的阳性表达依次减低为68%、42%、30%.结论:塞来昔布能够有效抑制大鼠OIR模型视网膜新生血管的生长,且抑制效果与剂量正相关,其作用可能通过抑制VEGF表达实现.     

氧诱导视网膜新生血管模型小鼠中ephrin A家族基因的表达

目的 观察ephrin A家族的基因是否参与氧诱导的小鼠视网膜新生血管(RNV)形成.方法 利用氧诱导新生小鼠C57BL/6J制备氧诱RNV模型,用逆转录聚合酶链式反应(RT-PCT)检测ephrin A1～A5在模型组小鼠视网膜和同龄正常小鼠(对照组)视网膜中的表达.结果 ephrin A1～A5mRNA均在正常视网膜发育的某一阶段或者发育的全程表达.在模型组小鼠视网膜中,ephrin A1 mRNA的表达量相对于对照组小鼠明显上调(t=3.19,P=0.019);ephrin A2 mRNA的表达量在15日龄的模型组小鼠中相对于对照组小鼠显著上调(t=3.71,P=0.033);ephrin A3～A5 mRNA在12、13日龄的模型组小鼠视网膜中相对于对照组小鼠表达下调或者缺失,而在15日龄的模型组小鼠视网膜相对于对照组小鼠视网膜显著上调(t=3.785,P=0.002).结论 ephrin A家族的基因参与视网膜的发育和视网膜病理性血管生成等重要的生理和病理过程.     

眼底荧光素血管造影在小鼠氧诱导视网膜病变中的应用评价

目的：：在小鼠氧诱导视网膜病变模型( oxygen-induced retinopathy,OIR )中评价眼底荧光素血管造影( fundus fluorescein angiography,FFA)的应用价值。方法：将前期实验证实视网膜病变严重程度有明显差异的两组( B组>A组)各12只新生幼鼠于出生后第7 d置于75％浓度氧环境中,第12 d时返回正常空气环境中饲养。第17 d时将A组和B组的幼鼠均随机分配,分别进行FFA检查或高分子量FITC-Dextran灌注结合视网膜铺片检查,即每种检查方法纳入两组幼鼠各6只,利用图像分析软件对视网膜无灌注区进行定量分析和比较。结果：FFA结合图像分析软件能对视网膜无灌注区进行定量分析,与FITC-Dextran灌注结合视网膜铺片的测量结果有良好的可比性,两种方法得到的结果无统计学差异(P>0.05)。结论：FFA结合图像定量分析在小鼠OIR模型的血管病变评价中具有一定的实用价值。     

氧诱导视网膜新生血管模型小鼠中ephrin A家族基因的表达

目的 观察ephrin A家族的基因是否参与氧诱导的小鼠视网膜新生血管(RNV)形成.方法 利用氧诱导新生小鼠C57BL/6J制备氧诱RNV模型,用逆转录聚合酶链式反应(RT-PCT)检测ephrin A1～A5在模型组小鼠视网膜和同龄正常小鼠(对照组)视网膜中的表达.结果 ephrin A1～A5mRNA均在正常视网膜发育的某一阶段或者发育的全程表达.在模型组小鼠视网膜中,ephrin A1 mRNA的表达量相对于对照组小鼠明显上调(t=3.19,P=0.019);ephrin A2 mRNA的表达量在15日龄的模型组小鼠中相对于对照组小鼠显著上调(t=3.71,P=0.033);ephrin A3～A5 mRNA在12、13日龄的模型组小鼠视网膜中相对于对照组小鼠表达下调或者缺失,而在15日龄的模型组小鼠视网膜相对于对照组小鼠视网膜显著上调(t=3.785,P=0.002).结论 ephrin A家族的基因参与视网膜的发育和视网膜病理性血管生成等重要的生理和病理过程.     

氧诱导视网膜新生血管模型小鼠中ephrin A家族基因的表达

目的 观察ephrin A家族的基因是否参与氧诱导的小鼠视网膜新生血管(RNV)形成.方法 利用氧诱导新生小鼠C57BL/6J制备氧诱RNV模型,用逆转录聚合酶链式反应(RT-PCT)检测ephrin A1～A5在模型组小鼠视网膜和同龄正常小鼠(对照组)视网膜中的表达.结果 ephrin A1～A5mRNA均在正常视网膜发育的某一阶段或者发育的全程表达.在模型组小鼠视网膜中,ephrin A1 mRNA的表达量相对于对照组小鼠明显上调(t=3.19,P=0.019);ephrin A2 mRNA的表达量在15日龄的模型组小鼠中相对于对照组小鼠显著上调(t=3.71,P=0.033);ephrin A3～A5 mRNA在12、13日龄的模型组小鼠视网膜中相对于对照组小鼠表达下调或者缺失,而在15日龄的模型组小鼠视网膜相对于对照组小鼠视网膜显著上调(t=3.785,P=0.002).结论 ephrin A家族的基因参与视网膜的发育和视网膜病理性血管生成等重要的生理和病理过程.