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。

Effect of the dipeptide Arg-Gln on retinopathy of prematurity in mice

·AIM: To investigate the effect of the dipeptide Arg-Glnon retinal neovascularization of retinopathy of prematurity(ROP) in the oxygen-induced retinopathy (OIR) animalmodel.·METHODS.- Forty-eight 7-day-old C57BL/6J mice were exposed to 750mL/L oxygen for 5 days and then to normal situation to produce the murine model of oxygen-induced retinopathy (OIR). All mice received twice daily intra- peritoneal injections of PBS or the dipeptide Arg-Gln(1.0, 3.0, 5.0g/kg per day), starting on postnatal day 12 and continuing till postnatal day 17. Experimental groups (36 mice, 12 in each group) received Arg-Gln, while the control group (12 mice) received PBS. All mice were executed at postnatal day 17. The changes of retinal vessels of mice were observed by ADPase histochemical technique and HE staining was used to count preretinal neovascular nuclei. RNA was isolated from retinas of 28 mice (7 in each group) selected at random and VEGF mRNA level of each group was measured by real-time RT-PCR.·RESULTS; Neovascularization reduced in retinas of the dipeptide Arg-Gln treated group in a dose-dependent manner. Compared with control group, experimental group had diminished non-perfusion area and neovascular tufts in retinal flatmount. The number of the endo-theliocyte nuclei of new vessels extending from retina to vitreous was significantly less in the eyes of the experimental group than in control group. Arg-Gln at 5g/kg per day reduced preretinal neovascularization by about 75% (P＜ 0.01). There was a significant reduction in VEGF mRNA at the 17th day in Arg-Gln treated group compared with control group(P＜0.01).·CONCLUSION; Arg-Gln dramatically inhibits retinal angiogenesis in OIR and this effect is associated with a reduction in retinal VEGF mRNA level. It appears to be a safe way to prevent and treat some neovascular retinal diseases including retinopathy of prematurity.