【摘要】 目的:探讨生后不同时间和不同剂量N-甲基-N-亚硝基脲(MNU)对小鼠视网膜发育和玻璃体血管系统退化的影响及其相互关系。方法:MNU单次腹腔注射制备小鼠视网膜发育不良模型,取左侧眼球切片后行H-E染色,观察眼球主要结构的形态改变,取右侧眼球玻璃体血管铺片后行DAPI染色,进行玻璃体血管定量分析。结果:高剂量MNU(75 mg/kg)在P1及P9给药,对视网膜发育及玻璃体退化影响有差异。在P1给药时,出现小眼球畸形和晶状体后瘢块;视网膜因视细胞呈玫瑰花结样排列而形成皱襞样结构,至P18~P28,视网膜皱襞逐渐消失,P28后仅表现为外核层的局部不规则。在P9给药时,除在P28后仍有玻璃体动脉束残留外,未见视网膜退变和其他眼部病理改变,但玻璃体血管定量分析显示直到P42仍有退化血管残留。结论:高剂量MNU(75 mg/kg)能诱导新生小鼠视网膜发育不良,且视网膜发育不良和玻璃体退化延迟在发生时间上存在相关性,提示感光细胞发育障碍对玻璃体血管退化具有一定作用。更多还原

【Abstract】 Objective: To explore the relationship between retinal development and hyaloid regression by investigating the influence of different dosages of N-methyl-N-nitrosourea(MNU) administration on developing retina and regressing hyaloid vessels in neonatal mice.Methods: The mice were injected with single dose of MNU intraperitoneally.Sections were obtained from the left eyeballs for histological studies and wholemounts of hyaloid vessels prepared from the right eyeballs were stained with DAPI for quantitative analysis.Results: The histological examination in mice injected with high dose of MNU(75mg/kg) at P1 showed the features like microphthalmia,retrolenticular tissue,and retinal rosettes resembling the PHPV.In mice injected with MNU(75mg/kg) at P9 retinal degeneration and other ocular pathology were not manifested,however,older than 28 days mice showed HA stalk in H-E sections.The quantitative analysis of hyaloid vessels in these mice indicated the prolonged time course of hyaloid regression lasting up to 42 days of age.Conclusion: This study demonstrated that 75mg/kg dose of MNU at P1 sufficiently induces retinal dysplasia for temporary period in newborn mice and its administration at P9 delays the hyaloid vascular regression,indicating the possible role of developing photoreceptor cells in the involution of hyaloid vessels.更多还原