Effects of aminoguanidine on retinal apoptosis in mice with oxygen-induced retinopathy

AIM: To explore the protective effects of aminoguanidine (AG) on retinal apoptosis in mice with oxygen-induced retinopathy (OIR).METHODS:A total of 80 C57BL/6J mice, aged 7 days, were randomly divided into four groups:normal, high oxygen, high oxygen saline and high oxygen treated with AG. In the normal group, mice were housed in normoxic conditions from postnatal day P7 to P17. Mice in the other 3 groups were placed under hyperoxic conditions (75±2%O2) in an oxygen-regulated chamber for 5 days and subsequently placed in normoxic conditions for 5 days. Mice in the AG group were treated once daily, from P12 to P17, with AG hemisulfate (100mg/kg body weight, intraperitoneally) dissolved in physiological saline. An equivalent amount of 0.9% physiological saline was administered, as above, to mice in the high oxygen saline group. Ten mice were randomly selected from each group on P14 and on P17, euthanized and the retinas examined. Apoptotic cells in the retina were detected using the terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) method. The expression of nitric oxide synthase (iNOS) in the retina was detected by immunohistochemistry and changes in rod cells were observed using electron microscopy.RESULTS:TUNEL-positive cells and iNOS immunoreactive neurons were present in the inner nuclear and ganglion cell retinal layers of mice in the high oxygen group. The number of TUNEL-positive cells was significantly greater in the high oxygen group compared with the normal group (t=-20.81, P14d <0.05; t=-15.05, P17d<0.05). However, the number of TUNEL-positive cells in the AG treatment group was significantly lower (t=-13.21, P14d<0.05; t=-6.61,P17d <0.05) compared with the high oxygen group. The expression of iNOS was significantly higher in the high oxygen group compared with the normal group (t=-21.95, P14d<0.05; t=-17.30, P17d<0.05). However, the expression of iNOS in the AG treatment group was significantly lower (t=-12.17,P14d<0.05; t=-10.30,P17d<0.05) compared with the high oxygen group. The outer segments of the rods were disorganized and short in the high oxygen group. Rod morphology appeared to be slightly improved in the AG group.CONCLUSION:AG may protect retinal neurons in OIR by inhibiting apoptosis. The mechanism may be related to iNOS.     

多巴胺对氧诱导视网膜病变小鼠视网膜新生血管的影响

目的 观察多巴胺(DA)及多巴胺D2受体(DRD2)在氧诱导视网膜病变(OIR)小鼠模型中对视网膜新生血管的作用。方法 随机将180只小鼠分为空白组、OIR组、NaCl组、DA组、Quinpirole(DRD2激动剂)组、Spiperone(DRD2抑制剂)组,每组30只。空白组小鼠在正常环境中饲养,其他各组小鼠在7 d龄时于高氧环境中饲养5 d,于小鼠12 d龄时返回正常环境中,OIR组不做药物干预,NaCl组、DA组、Quinpirole组分别于小鼠右眼玻璃体内注射8.5 g·L^-1 NaCl、15 mmol·L^-1的DA溶液、602μmol·L^-1的Quinpirole溶液,Spiperone组小鼠右眼玻璃体内依次注射154μmol·L^-1的Spiperone溶液和15 mmol·L^-1的DA溶液各1μL。小鼠17 d龄时处死,摘取右侧眼球进行后续实验。采用苏木精-伊红(HE)染色和视网膜铺片检查各组小鼠视网膜新生血管情况;采用Q-PCR和Western blot检测各组...     

一种精确评估氧诱导小鼠视网膜新生血管和无灌注区的联合方法

目的 探讨异硫氰酸荧光素-葡聚糖(FITC-Dextran)联合异凝集素(isolectin B4)在评估氧诱导视网膜病变(oxygen-induced retinopathy,OIR)小鼠视网膜新生血管和无灌注区中的作用.方法 10只生后第17天的OIR小鼠分别眶后注射FITC-Dextran,取出视网膜行isolectin B4染色,应用Image Pro-Plus 5.1软件测量视网膜新生血管、无灌注区及整个视网膜面积,计算视网膜新生血管和无灌注区占整个视网膜面积的百分比并比较.结果 FITC-Dextran评估的视网膜新生血管占整个视网膜面积的百分比为(0.100 9±0.001 0)％,均小于FITC-Dextran联合isolectin B4的(0.1046±0.001 0)％或isolectin B4的(0.104 9±0.0020)％(均为P＜0.01).FITC-Dextran评估的视网膜无灌注区占整个视网膜面积的百分比为(0.285 0±0.001 0)％,均大于FITC-Dextran联合isolectin B4的(0.266 8±0.001 0)％或isolectinB4的(0.267 6±0.002 0)％(均为P＜0.01).FITC-Dextran联合isolectin B4比isolectin B4更易于鉴别视网膜铺片上残留的玻璃体血管,比FITC-Dextran更易于发现未充盈的视网膜小血管.结论 FITC-Dextran联合isoleetin B4视网膜血管染色比FITC-Dextran或isolectin B4更能精确评估视网膜新生血管和无灌注区面积.     

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.     

Arresten在氧诱导小鼠视网膜新生血管形成中的抑制作用及机制

目的　探讨Arresten在氧诱导小鼠视网膜新生血管形成中的抑制作用及机制。方法　选取48只出生后7 d健康清洁级C57BL/6J幼鼠,随机分为氧诱导视网膜病变（oxygen induced retinopathy,OIR）组、OIR+ Arresten组和常氧组,每组16只。OIR+Arresten组及OIR组幼鼠在体积分数为（75±2）％的高氧环境下饲养5 d,然后转移至正常氧气环境中饲养5 d,其中OIR+Arresten组幼鼠于高氧饲养刚结束时,给予双眼玻璃体内注射Arresten蛋白。常氧组幼鼠则在常规氧气环境中连续饲养10 d。在鼠龄17 d时,各组取6只幼鼠经股静脉注射异硫氰酸葡聚糖溶液处死并摘出眼球,视网膜铺片后观察视网膜的血管形态、计算无灌注区面积。同时对小鼠眼球视网膜行石蜡切片和HE染色,计算侵入玻璃体内血管内皮细胞核的数量。同时,通过细胞培养实验,利用MTT法检测Arresten蛋白对人血管内皮细胞增殖的抑制作用。结果　视网膜铺片结果显示,常氧组、OIR组、OIR+Arresten组视网膜无灌注区相对面积分别为（2.35±1.62）％、（57.28±9.36）％和（20.38±8.69）％,三组间总体比较,差异有统计学意义（F=18.732,P<0.05）,且OIR组无灌注区相对面积显著高于OIR+Arresten组,差异有统计学意义（P<0.05）。常氧组小鼠视网膜的内界膜结构仍保持平滑完整,未发现有新生血管侵入玻璃体内。OIR组和OIR+Arresten组每张切片上血管内皮细胞核的数量分别为 （15.18±4.83）个、（7.33±3.88）个,其中OIR+Arresten组侵入玻璃体内新生血管内皮细胞核的数量显著低于OIR组,差异有统计学意义（P<0.05）。Arresten蛋白对人脐静脉内皮细胞增殖的抑制率随着其浓度的升高而增加,但当Arresten蛋白浓度达到1000 μg·L^-1时,人脐静脉内皮细胞的增殖抑制率达到顶峰,为（58.00±0.65）％。结论　Arresten蛋白能够抑制氧诱导的小鼠视网膜新生血管形成,通过抑制血管内皮细胞增殖来抑制新生血管形成。     

TERT基因siRNA抑制鼠视网膜新生血管形成的研究

目的 探讨小鼠端粒酶逆转录酶(TERT)小分子干扰RNA(siRNA)对小鼠视网膜新生血管形成的抑制作用,及其用于视网膜新生血管疾病治疗的可行性.方法构建TERT siRNA重组质粒pSIREN-mTERT-1和阴性对照质粒pStREN-mTERT-N.选择7 d龄C57BL/6J小鼠80只随机分为基因治疗组、阴性质粒组、高氧对照组及正常对照组,每组20只.前3组置于75%±2%高氧环境中生活5 d,然后回到正常氧环境中.于第12天出氧舱时,分别向基因治疗组、阴性质粒组两组小鼠玻璃体腔内注射上述两种质粒.正常对照组小鼠正常氧环境中饲养.高氧对照组和正常对照组不予玻璃体腔注射.第19天用2%Evens蓝灌注进行视网膜铺片,观察各组小鼠视网膜血管形态变化;反转录-PCR及Real-time PCR检测各组间TERT mRNA和新生血管相关基因的表达变化;组织切片观察并计数突破内界膜的血管内皮细胞数量.对数据采用单因素方差分析进行统计学比较.结果 荧光造影视网膜铺片显示,基因治疗组整个视网膜血管分布网基本正常,走形较自然,基本接近正常对照组,未见明显的新生血管丛及大片荧光渗漏,只在视网膜中周部及周边部见少许荧光渗漏,但较阴性质粒组及高氧对照组明显减少.阴性质粒组及高氧对照组视网膜血管紊乱,中周部血管迂曲,伴大片荧光渗漏.RT-PCR及实时PCR显示基因治疗组小鼠视网膜TERT mRNA表达为0.56±0.32,明显少于阴性质粒组及高氧对照组(P＜0.05).组织切片HE染色观察,基因治疗组仅见1处新生血管芽,偶见突出内界膜的细胞核;阴性质粒组及高氧对照组见散在突出内界膜伸向玻璃体腔的血管芽,内界膜下出现明显的血管内皮细胞增生;光镜下观察突破内界膜新牛血管内皮细胞计数,基因治疗组(14.62±1.70)较阴性质粒组(32.38±7.50)及高氧对照组明显减少,差异有统计学意义(P＜0.05).结论 TERT特异的siRNA能有效地抑视网膜新生血管动物模鼎视网膜中视网膜新生血管的形成,可能会成为一种治疗视网膜新生血管疾病的新方法.     

靶向血管内皮生长因子的RNA干扰抑制氧诱导视网膜病变小鼠视网膜新生血管生成的研究

目的探讨玻璃体腔注射靶向血管内皮生长因子（VEGF）的RNA干扰慢病毒抑制氧诱导视网膜病变（OIR）小鼠视网膜新生血管生成的作用及其机制。方法实验研究。构建4对针对靶基冈小鼠VEGF的siRNA干扰载体,筛选并进行慢病毒包装。60只C57Bif6J小鼠分成4组（每组15只）：正常对照组．OIR模型组,OIR＋空载体组,OIR＋VEGF-RNA干扰组。OIR＋空载体组和OIR＋VEGF-RNA干扰慢病毒组的小鼠在生后第5天玻璃体腔注射相应的1μ1的7.5×10^7空载体慢病毒和VEGF-RNA干扰慢病毒。后3组小鼠在生后第7天建立OIR模型。第17天时FITC-Dextran灌注视网膜铺片观察4组小鼠视网膜血管形态及面积变化,视网膜铺片免疫荧光染色检测紧密连接蛋白Claudin-5和Occludin的分布变化．Westernblot检测VEGF、磷酸肌醇3激酶（P13K）、酪氨酸蛋白激酶SRC、磷酸化细胞外信号调节激酶（P-ERK）蛋白表达量的变化。数据采用单因素方差分析进行比较。结果FITC-Dextran灌注视网膜铺片显示正常组视网膜血管分布呈均匀网状;RNA干扰组新生血管面积（0．271399mm^2）明显较OIR模型组（1.212782mm^2）、空载体组（1．152504mm^2）少（F=449．924,P〈0．01）。OIR模型组和空载体组间差异无统计学意义,其余两两间差异均有统计学意义（P〈0．01）。视网膜铺片免疫荧光染色显示紧密连接蛋白Claudin-5和Occludin在RNA干扰组中与正常组相似,呈均匀光滑线性分布,而在OIR模型组、空载体组的分布中断、不均匀,在新生血管团中可见团块状的强荧光;VEGF的RNA干扰组中VEGF、P13K、酪氨酸蛋白激酶SRC和p-ERK的蛋白表达量较OIR模型和空载体组低。结论玻璃体腔注射靶向VEGF的RNA干扰慢病毒能有效抑制OIR小鼠模型中VEGF及其下游通路蛋白的表达．从而抑制视网膜新生血管的形成．为临床上早产儿视网膜病变的防治提供了新思路和新途径。     

Suppression of retinal neovascularization by the NF-kappaB inhibitor pyrrolidine dithiocarbamate in mice.

PURPOSE: To evaluate the effect of pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor kappaB (NF-kappaB), on retinal neovascularization in a murine model of ischemic retinopathy. METHODS: One-week-old C57BL/6N mice were exposed to 75%+/-2% oxygen for 5 days and then were returned to room air to induce retinal neovascularization. After the return to room air, the left and right eyes were injected intravitreally with PDTC or a vehicle, respectively. Retinal neovascularization was examined by injecting fluorescein dextran and angiography after 5 days in room air and was quantitated histologically with a masked protocol. The effects of PDTC on NF-kappaB activation were evaluated by immunohistochemistry. To examine the toxicity of PDTC, the histologic change in the retina was examined by light and electron microscopy. RESULTS: Retinal neovascularization in the eye injected with PDTC by intravitreal methods was reduced in 100% of animals compared with that apparent in the vehicle-treated eye. The inhibitory effect was dose-dependent, with a maximal inhibition of 39% (P < 0.01) at a dose of 1 nmole. The immunostaining intensity for NF-KB in the retina was reduced by PDTC injections. No side effects by PDTC in the retina were observed by light and electron microscopy. CONCLUSIONS: NF-kappaB activation appears to be required for retinal angiogenesis, given that the administration of PDTC suppressed retinal neovascularization. PDTC may prove beneficial in the treatment of ischemic neovascular diseases such as diabetic retinopathy and retinal vein occlusion.     

慢病毒介导聚嘧啶束结合蛋白相关剪接因子对氧诱导视网膜病变小鼠视网膜新生血管的抑制作用

目的观察慢病毒介导聚嘧啶束结合蛋白相关剪接因子(PSF)对氧诱导视网膜病变(OIR)小鼠视网膜新生血管的抑制作用。方法5日龄C57BL/6J小鼠112只随机分为正常对照组、单纯OIR模型组、OIR模型+慢病毒空载体处理组(以下简称Vec组)及OIR模型+PSF慢病毒处理组(以下简称PSF组),分别为16、32、32、32只。小鼠7日龄时,正常对照组小鼠常规环境饲养;单纯OIR模型组、Vec组及PSF组小鼠建立OIR模型。小鼠12日龄时,Vec组、PSF组小鼠玻璃体腔分别注射滴度为1×1011 TU/ml的空载体病毒或PSF慢病毒1μl。正常对照组和单纯OIR模型组小鼠不再做任何处理。小鼠17日龄时,采用HE染色计数突破视网膜内界膜的血管内皮细胞核;作视网膜铺片,测量各组小鼠视网膜无灌注区相对面积;采用实时定量PCR检测各组小鼠视网膜中NF-E2相关因子2(Nrf2)和血红素氧合酶1(HO-1)的mRNA相对表达量;采用Western blot检测各组小鼠视网膜中Nrf2、HO-1及PSF的蛋白相对表达量。组间比较采用单因素方差分析。结果正常对照组、单纯OIR模型组、Vec组、PSF组小鼠突破内界膜的血管内皮细胞核数分别为0.00、14.36±5.50、15.67±4.96、8.13±2.09个;视网膜无灌注区面积分别为0.00%、(35.71±2.81)%、(36.57±4.53)%、(15.33±4.75)%。4组间小鼠突破内界膜的血管内皮细胞核数及视网膜无灌注区面积比较,差异均有统计学意义(F=24.87、165.70,P<0.05)。组间两两比较,单纯OIR模型组、Vec组较正常对照组突破内界膜的血管内皮细胞核数增多,视网膜无灌注区面积增大;PSF组较单纯OIR模型组、Vec组突破内界膜的血管内皮细胞核数减少,视网膜无灌注区面积减小,差异均有统计学意义(P<0.05)。实时定量PCR及Western blot检测结果显示,4组间小鼠视网膜Nrf2、PSF mRNA相对表达量(F=53.66、83.54)以及Nrf2、HO-1、PSF蛋白相对表达量(F=58.38、52.69、24.79)比较,差异均有统计学意义(P<0.05)。组间两两比较,单纯OIR模型组、Vec组小鼠视网膜Nrf2、PSF mRNA相对表达量及Nrf2、HO-1、PSF蛋白相对表达量较正常对照组明显降低,PSF组小鼠视网膜Nrf2、PSF mRNA相对表达量及Nrf2、HO-1、PSF蛋白相对表达量较单纯OIR模型组、Vec组明显增加,差异均有统计学意义(P<0.05)。结论慢病毒介导的PSF可通过上调Nrf2及HO-1的表达抑制OIR小鼠视网膜新生血管形成。     

氧诱导视网膜病变动物模型在视网膜新生血管治疗中的应用

氧诱导视网膜病变(oxygen-induced retinopathy,OIR)模型是研究视网膜新生血管常用的动物模型,多种治疗视网膜新生血管的研究,如与氧自由基相关药物、与血管内皮生长因子相关的药物等都使用了OIR模型.近年来干细胞治疗视网膜新生血管成为研究的热点,OIR模型又被广泛使用,并取得了满意结果.     

Acetylcholinesterase inhibition ameliorates retinal neovascularization and glial activation in oxygen-induced retinopathy

AIM: To investigate whether inhibition of acetylcholinesterase (AChE) by donepezil ameliorate aberrant retinal neovascularization (RNV) and abnormal glial activation in oxygen-induced retinopathy (OIR). METHODS: A mouse model of RNV was induced in postnatal day 7 (P7) mice by exposure to 75% oxygen. Donepezil was administrated to P12 mice by intraperitoneal injection. Expression and localization of AChE in mouse retinas were determined by immunofluorescence. RNV was evaluated by paraffin sectioning and hematoxylin and eosin (HE) staining. Activation of retinal Müller glial cells were examined by immunoblot of glial fibrillary acidic protein (GFAP). rMC-1, a retinal Müller cell line, was used for in vitro study. Expression of hypoxia-induced factor 1α (HIF-1α) and vascular endothelial growth factor (VEGF) were determined by Western-blot analysis, enzyme-linked immunosorbent assay (ELISA) or immunostaining. RESULTS: Aberrant RNV and glial activation was observed after OIR. Of note, retinal AChE was mainly expressed by retinal Müller glial cells and markedly increased in OIR mice. Systemic administration of donepezil significantly reduced RNV and abnormal glial activation in mice with OIR. Moreover, ischemia-induced HIF-1α accumulation and VEGF upregulation in OIR mouse retinas and cultured rMC-1 were significantly inhibited by donepezil intervention. CONCLUSION: AchE is implicated in RNV with OIR. Inhibition of AChE by donepeizl is likely to be a potential therapeutic approach for retinal neovascular diseases.     

内皮抑素抑制氧致视网膜病变小鼠 新生血管形成的实验研究

目的观察血管生成抑制因子内皮抑素（ES）对视网膜新生血管形成的抑制作用。方法将鼠龄为7 d的32只C57BL/6J小鼠随机分为给氧组（12只）、ES治疗组（12只）和对照组（8只）。将给氧组和ES治疗组小鼠置于浓度为（75±5）％高氧环境中生活5 d，然后回到正常氧环境中。ES治疗组小鼠在出氧箱后12、36 h，一只眼玻璃体腔内注射1μgES，另一只眼注射1 μl的磷酸盐缓冲溶液（PBS）作为对照。对照组小鼠生活在正常氧环境中。右旋糖苷-异硫氰酸荧光素（FITC-dextran）视网膜造影整装铺片了解视网膜新生血管改变；计数突破内界膜的内皮细胞数反映视网膜血管增生情况，观察ES对视网膜新生血管形成的抑制作用。结果与给氧组相比，ES治疗组视网膜铺片见视网膜血管分支走行正常，未见明显的无灌注区；ES治疗眼平均每个视网膜切面可见突破内界膜的内皮细胞核数减少，为（5.39±1.52）个，与给氧组［（22.56±2.13）个］比较，差异有统计学意义（P<0.001）。结论ES可有效抑制视网膜新生血管的形成，有望成为治疗血管增生性视网膜病变的新途径。(中华眼底病杂志,2005,21:314-317)     

The dipeptide Arg-Gln inhibits retinal neovascularization in the mouse model of oxygen-induced retinopathy

PURPOSE: Premature infants undergoing intensive care are highly vulnerable to amino acid deprivation. Supplementation of glutamine or arginine has resulted in beneficial effects in human neonates. This study was conducted to examine the effect of the dipeptide arginyl-glutamine (Arg-Gln) on vascular endothelial cell growth factor (VEGF) levels in primary human retinal pigment epithelial (hRPE) cell cultures and on inhibition of neovascularization in the oxygen-induced retinopathy (OIR) model. METHODS: The effects of Arg-Gln on VEGF levels were measured in supernates from hRPE cells by using ELISAs. For in vivo studies, mouse pups received twice-daily intraperitoneal injections of Arg-Gln, a control dipeptide (Ala-Gly) or were not injected. Retinal flatmounts from one cohort were prepared and retinal vessel morphology examined. The contralateral eyes were embedded, sectioned, and stained to count preretinal neovascular nuclei. RNA was isolated from retinas of selected animals and was used to quantify VEGF mRNA by real-time RT-PCR. RESULTS: Treatment of hRPE cells with Arg-Gln decreased VEGF levels in a dose-dependent manner. In the OIR model, Arg-Gln at 5 g/kg per day reduced preretinal neovascularization by 82%+/-7% (P<0.005), when compared with the control dipeptide Ala-Gly, and reduced VEGF mRNA by 64%+/-9% (P<0.001). CONCLUSIONS: Arg-Gln dramatically inhibited retinal neovascularization in the OIR model. This effect was associated with a reduction in retinal VEGF mRNA levels. Similarly the dipeptide reduced VEGF expression in hRPE cells, a cell type likely to respond to retinal hypoxia by expressing VEGF. Arg-Gln appears to be safe and, with future studies in human infants, may prove beneficial in the prevention of ROP.     

地塞米松抑制碱烧伤后角膜新生血管的实验研究

目的：探讨地塞米松对角膜新生血管形成及角膜内血管内皮生长因子（ＶＥＧＦ）的影响。方法：采用碱烧伤的方法制备家兔角膜新生血管模型,分为三组,每日结膜下注射地塞米松０．５毫克组、１．０毫克组、对照组。分别采用宏观测量新生血管长度及生长速度,免疫组化染色检查ＶＥＧＦ蛋白的表达,显微镜下微血管计数方法研究角膜新生血管形成及抑制情况。结果：实验组新生血管生长速度变慢,微血管数量减少,ＶＥＧＦ蛋白表达下降,具     

抗血管内皮生长因子单克隆抗体Bevacizumab抑制氧致视网膜病变模型鼠新生血管

目的 观察抗血管内皮生长因子单克隆抗体Bevacizumab 对氧致视网膜病变模型鼠视网膜新生血管的抑制作用。 方法 7日龄C57BL/6J幼鼠90只，数字表法随机分为4组：1 组15只，为正常对照组；2组15只，为给氧对照组；3组30只，为大剂量Bevacizumab治疗组 ；4组30只，为小剂量Bevacizumab治疗组。其中，2、3、4组置于氧浓度（75±2）%的容器内连续饲养至12日龄，再置于正常空气下饲养。第12天3、4组幼鼠玻璃体腔分别注射Bevacizumab 2、1 μl，对侧眼注射相同体积的平衡盐溶液作为对照。二磷酸腺苷酶染色法进行 视网膜铺片,了解视网膜血管改变；视网膜切片染色，计数小鼠视网膜新生血管内皮细胞核数；逆转录聚合酶链反应（RT-PCR）检测血管内皮生长因子（VEGF） mRNA的表达。 结果 与给氧对照组比较, Bevacizumab治疗组视网膜血管分布规则、密度减少,突破视网膜内界膜的内皮细胞核数目明显减少(P＜0.001),但不同剂量治疗组间比较，差异无统计学意义 (P＞0.05) ；给氧组无论是否采用Bevacizumab治疗，也不论Bevacizumab剂量大小，其VEGF的mRNA表达 量比较，差异均无统计学意义（P＞0.05）。 结论 抗VEGF单克隆抗体Bevacizumab能有效抑制氧致视网膜病变模型鼠视网膜新生血管的形成，可能成为治疗氧致视网膜病变等早产儿视网膜病变的一种新方法。 （中华眼底病杂志，2008，24：184-188）     

玻璃体腔注射熊果酸对小鼠氧诱导视网膜新生血管的抑制作用

背景 视网膜新生血管疾病严重影响视功能,目前虽然有较多的抗新生血管药物,但多针对单一的干预靶点,疗效有限.研究证实,熊果酸具有多种生物学效应,其中包括抗血管新生作用,但其对眼科血管疾病的疗效尚不清楚. 目的 观察熊果酸对小鼠氧诱导视网膜新生血管形成的抑制作用. 方法 采用随机数字表法将7日龄清洁级C57BL/6J小鼠60只随机分为6个组,即空白对照组、PBS对照组、阳性对照组和低、中、高剂量熊果酸组.空白对照组小鼠在正常环境中喂养,其他各组小鼠与哺乳的母鼠置于体积分数(75±2)％的高氧环境中连续饲养5d,小鼠12日龄时将模型小鼠及其哺乳母鼠返回正常空气环境中,以诱导视网膜新生血管产生.造模成功后按照分组不同分别于小鼠玻璃体腔注射无菌PBS 3μl、曲安奈德注射液(1 ml∶40 mg)3μl或1.5、3.0、6.0μg熊果酸各3μl.小鼠17日龄时过量麻醉法处死,摘除双侧眼球制备视网膜组织切片.采用组织病理学方法检查各组小鼠视网膜血管新生情况,计数突破视网膜内界膜的新生血管内皮细胞核数目;采用逆转录PCR(RT-PCR)法分别检测和比较各组小鼠视网膜组织中血管内皮生长因子(VEGF) mRNA、环氧合酶-2(COX-2)mRNA及基质金属蛋白酶-2(MMP-2)mRNA的相对表达量. 结果 视网膜切片后苏木精-伊红染色显示,PBS对照组小鼠视网膜中突破内界膜的新生血管内皮细胞核数为(18.65±3.24)个/视野,明显高于空白对照组的(0.78±0.11)个/视野,差异有统计学意义(t=2.24,P＜0.05);中剂量熊果酸组、高剂量熊果酸组小鼠视网膜突破内界膜的新生血管内皮细胞核数分别为(13.32±1.87)个/视野和(8.93±1.09)个/视野,明显少于PBS对照组和低剂量熊果酸组的(18.65±3.24)个/视野和(15.44±2.02)个/视野,差异均有统计学意义(均P＜0.05),而高剂量熊果酸组小鼠视网膜突破内界膜的新生血管内皮细胞核数与阳性对照组的(9.14±1.13)个/视野接近,差异无统计学意义(t=1.17,P＞0.05).RT-PCR检测表明,PBS对照组小鼠视网膜组织中COX-2 mRNA、VEGF mRNA和MMP-2 mRNA相对表达量均明显高于空白对照组,差异均有统计学意义(t=13.45、12.49、14.32,均P＜0.05),且高剂量熊果酸组小鼠视网膜组织中COX-2mRNA、VEGF mRNA和MMP-2 mRNA相对表达量均明显低于PBS对照组和低剂量熊果酸组,差异均有统计学意义(均P＜0.05),而高剂量熊果酸组与阳性对照组间的差异均无统计学意义(均P＞0.05).结论 熊果酸以剂量依赖的方式下调氧诱导的缺血小鼠视网膜组织中VEGF、COX-2及MMP-2的表达,从而抑制视网膜新生血管的产生.     

MMP-2和PEDF在氧诱导小鼠视网膜新生血管中的表达

目的探讨基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)和色素上皮衍生因子(pigment epithelium derived factor,PEDF)在氧诱导小鼠视网膜新生血管中的表达和意义。方法随机选取80只健康C57BL/6J小鼠进行分组,取对照组(40只)和高氧组(40只)小鼠眼球作ADP酶视网膜铺片、病理切片及免疫组织化学法检测,观察视网膜血管的改变,计算视网膜新生血管突破内界膜的内皮细胞核数及检测MMP-2、PEDF蛋白的表达。结果高氧组视网膜大量新生血管形成;新生血管突破内界膜的内皮细胞核数为(32.45±1.34)个,与对照组(1.27±0.20)个相比差异有统计学意义(t=10.345,P<0.05)。高氧组与对照组相比,MMP-2蛋白在神经节细胞层、内丛状层、内核层和突破视网膜内界膜的新生血管中高表达(P<0.05);PEDF蛋白在神经纤维层、神经节细胞层、内丛状层、感光细胞层及视网膜色素上皮细胞层低表达(P<0.05)。两者表达呈显著负相关(r=-0.785,P<0.05)。结论 MMP-2和PEDF共同维持视网膜新生血管的形成。