曲安奈德玻璃体腔注射对氧诱导视网膜新生血管的抑制作用及机制

目的 观察曲安奈德(TA)玻璃体腔注射对氧诱导视网膜新生血管的抑制作用,探讨其作用机制.方法 7日龄C57BL/6新生小鼠48只,随机分为正常对照组、单纯高氧组、TA正常组及TA高氧组,分别为6、6、18、18只.单纯高氧组及TA高氧组建立氧诱导视网膜新生血管模型.选取TA正常组及TA高氧组小鼠1只眼,玻璃体腔注射20μg/μl的TA 2 μl；对侧眼注射相同体积的平衡盐溶液(BSS)作为BBS正常组和BBS高氧组.小鼠17日龄时,各组作石蜡切片苏木精-伊红(HE)染色,观察并统计每张切片突破视网膜内界膜的血管内皮细胞核数.TA正常组、BSS正常组、TA高氧组及BSS高氧组作石蜡切片免疫组织化学染色,检测血管内皮生长因子(VEGF)、基质细胞衍生因子1(SDF-1)及CD14的平均吸光度[A,旧称光密度(OD)]值.并行荧光实时定量聚合酶链反应(PCR),检测VEGF及SDF-1的mRNA表达.结果 正常对照组、单纯高氧组、TA正常组、BSS对照组、TA高氧组及BSS高氧组突破视网膜内界膜的血管内皮细胞核数分别为0、675、0、0、110及688个.正常对照组较单纯高氧组明显减少,差异有统计学意义(t=30.62,P＜0.05).TA高氧组较BSS高氧组显著减少,差异有统计学意义(t=19.532,P＜0.05).TA正常组与BSS正常组VEGF、SDF-1及CD14平均A值比较,差异无统计学意义(t=0.161,0.284,0.223；P＞0.05).TA高氧组VEGF、SDF-1及CD14平均A值较BSS高氧组减少,差异有统计学意义(t=-2.264,-2.358,-4.897；P＜0.05).TA正常组与BSS正常组VEGF及SDF-1 mRNA表达比较,差异无统计学意义(t=-0.497,-0.709;P＜0.05).TA高氧组与BSS高氧组VEGF及SDF-1 mRNA表达比较,差异均有统计学意义(Z=-5.137,-4.411；P＜0.05).结论 玻璃体腔注射TA能有效抑制氧诱导视网膜新生血管形成,其抑制作用可能是通过降低VEGF及SDF-1的表达而实现.

Intravitreal injection of triamcinolone acetonide inhibits oxygen-induced retinal neovascularization

Objective To observe the inhibitory effect of intravitreal injection of triamcinolone acetonide (TA) on oxygen-induced retinal neovascularization,and to investigate its mechanism.Methods A total of 48 C57BL/6 mice at the age of 7 days were divided into normal group (group A,n=6),high-oxygen group (group B,n=6),TA control group (group C,n=18) and TA high-oxygen group (group D,n=18).The retinal neovascularization of group B and D were induced by oxygen.One eye of each mouse of group C and D received an intravitreal injection 2 μl (20 μg/μl) of TA,and the same volume of BSS was injected into the other eye of the mice as BSS control group (group E) and BSS high-oxygen group (group F).At postnatal day 17,the retinas were collected and the number of the endothelium cell nuclei of new vessels beyond the inner limiting membrane (ILM) was counted on HE-stained paraffin retina sections.The expression level of vascular endothelial growth factor (VEGF),stromal cell-derived factor 1 (SDF-1) and CD14 were measured by immunohistochemical staining.The mRNA expression of VEGF and SDF-1 were detected by real-time RT-PCR.Results The numbers of the endothelium cell nuclei of new vessels beyond the ILM in group A - F were 0,675,0,0,110 and 688 respectively.In group A and D,it decreased than that in group B and F respectively (t=30.62,19.532; P＜0.05).There was no difference of VEGF,SDF-1 and CD14 expression between group C and E (t=0.161,0.284,0.223 ; P＞0.05),but the differences were statistically significant between group D and F(t=-2.264,-2.358,-4.897;P＜0.05).There was no difference on mRNA level of VEGF and SDF-1 between group C and E(t =- 0.497,- 0.709 ; P＜0.05),but the differences were statistically significant between group D and F(z=-5.137,-4.411;P＜0.05).Conclusion Intravitreal injection with TA can inhibit oxygen-induced retinal neovascularization,downregulated expression of VEGF and SDF-1 may be the mechanism.