左卡尼汀对小鼠氧诱导视网膜病变保护作用的实验研究

发布时间：2018-06-10 15:41

本文选题：左卡尼汀 + 氧诱导视网膜病变　；参考：《青岛大学》2012年硕士论文

【摘要】：目的建立氧诱导视网膜病变(OIR)小鼠模型,观察高氧诱导的视网膜病理改变,并通过腹腔注射不同剂量的左卡尼汀,观察左卡尼汀是否对病变视网膜具有保护作用。方法选择7日龄C57BL/6J小鼠24只,随机分为正常对照组、高氧模型对照组、低剂量药物治疗组、高剂量药物治疗组,每组6只。除正常对照组外,其余组小鼠置于(75±2)%浓度的氧环境中饲养5天后,回到正常空气环境中饲养5天,建立氧诱导视网膜病变动物模型。对药物治疗组小鼠自7日龄起分别给予不同剂量的左卡尼汀,一次/天至小鼠17日龄。另两组给予相同体积的生理盐水。每组17日龄小鼠左眼行异硫氰酸葡聚糖荧光素(FITC-Dextran)灌注血管造影视网膜铺片观察视网膜血管形态变化。右眼石蜡切片行苏木精-伊红(HE)染色,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核数目,免疫组织化学染色观察血管内皮生长因子(VEGF)在视网膜各层的表达,脱氧核糖核苷酸末端转移酶介导缺口末端标记(TUNEL)染色,检测视网膜神经细胞凋亡数目。结果视网膜铺片结果显示,氧诱导视网膜病变模型鼠的视网膜中央及远周见无血管灌注区,周边部有大量新生血管形成；两治疗组均较高氧模型对照组视网膜血管分布均匀,新生血管和无灌注区显著减少。突破内界膜的内皮细胞核数：正常对照组为(0.4833±0.1169),高氧模型对照组为(33.85±2.53),两者比较有统计学意义(P0.01)；两治疗组分别为(19.03±4.43)、(12.37±1.62),与高氧模型对照组比较,组间差异具有统计学意义(F=76.059,P0.01)。两药物治疗组显著下调了VEGF的表达,高剂量药物治疗组效果显著。两治疗组与高氧模型对照组比较,视网膜神经细胞凋亡数目显著减少,组间差异具有统计学意义(P=129.199,P0.01)。结论氧诱导视网膜病变动物模型复制成功；左卡尼汀在一定程度上改善了OIR小鼠视网膜新生血管增殖情况并减少了视网膜神经细胞凋亡,从而对病变视网膜起保护作用。其机制可能与左卡尼汀抗氧化、清除氧自由基和抗凋亡作用有关。
[Abstract]:Objective to establish the model of oxygen-induced retinopathy (OIR) mice, observe the pathological changes of the retina induced by hyperoxia, and intraperitoneally inject levacarnitine with different doses. Methods 24 7-day-old C57BL / 6J mice were randomly divided into normal control group, hyperoxia model control group, low dose drug treatment group and high dose drug treatment group. In addition to the normal control group, the other mice were exposed to 75 卤2% oxygen for 5 days, then returned to the normal air for 5 days to establish the animal model of retinopathy induced by oxygen. The mice in the drug treatment group were given different doses of leucarnitine from 7 days old, once a day to 17 days old. The other two groups were given the same volume of saline. The left eye of each group of 17 days old mice were perfused with FITC-Dextranan (FITC-Dextranan) to observe the morphologic changes of retinal vessels. Paraffin sections of the right eye were stained with hematoxylin and eosin (HEH). The number of vascular endothelial nuclei breaking through the inner membrane of the retina was observed and counted under optical microscope. The expression of vascular endothelial growth factor (VEGF) in all layers of the retina was observed by immunohistochemical staining. Terminal deoxyribonucleotide transferase mediated Nick end labeling (Tunel) staining was used to detect the number of apoptosis in retinal neurons. In oxygen-induced retinopathy model rats, no vascularized area was found in the central and distal retina and a large number of neovascularization was found in the peripheral part of the retina, and the retinal vessels in the two treatment groups were more evenly distributed than those in the hyperoxia model control group. The neovascularization and no perfusion area decreased significantly. The number of endothelial nuclei breaking through the inner boundary membrane was 0.4833 卤0.1169 in the normal control group and 33.85 卤2.53 in the hyperoxia model control group, which was significantly higher than that in the control group (19.03 卤4.43) and the hyperoxia model group (12.37 卤1.62), respectively. The difference between the two groups was statistically significant compared with the hyperoxia model control group (P 0.01). The expression of VEGF was significantly down-regulated in the two drug treatment groups, and the effect was significant in the high-dose drug treatment group. Compared with the hyperoxia model control group, the number of apoptosis of retinal nerve cells in the two treatment groups was significantly decreased, and the difference between the two groups was statistically significant. Conclusion oxygen induced retinopathy animal model is successful. To a certain extent, L-carnitine improved retinal neovascularization and reduced retinal neuronal apoptosis in OIR mice. The mechanism may be related to the antioxidation, scavenging of oxygen free radicals and anti-apoptotic effects of leucarnitine.
【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R774.1

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