氪激光诱导的大鼠脉络膜新生血管模型研究

Study on the experimental model of krypton laser-induced choroidal neovascularization in the rats

目的 探讨氪激光创建棕色挪威 (brownnorway,BN)大鼠脉络膜新生血管 (choroidalneovascularization ,CNV)模型的可行性 ,为明确CNV的发生机制及防治研究奠定基础。方法 雄性BN大鼠 33只 (6 6只眼 ) ,取每只鼠一只眼作为实验眼 ,另一只眼为对照眼。用氪激光 (波长为 6 4 7nm)对大鼠实验眼视网膜进行光凝 ,激光功率、光凝斑直径和曝光时间分别为 36 0mW、5 0 μm及0 0 5s,每只眼10个光凝斑点。于光凝后 3、7、14、2 1、2 8及 5 6d行荧光素眼底血管造影 (fundusfluoresceinangiography ,FFA)和吲哚青绿血管造影 (indocyaninegreenangiography ,ICGA)检查后处死动物 ,摘除眼球制作标本 ,进行组织病理学及电镜观察。结果 光凝后 7d出现CNV ,2 1d达高峰 ,造模成功率为 76 0 % ,FFA检查显示典型圆盘状荧光渗漏 ,ICGA检查可见CNV充盈 ,光镜和电镜下均可见视网膜下CNV形成。CNV厚度自光凝后 7～ 2 1d逐渐增加 ,之后CNV厚度变化不显著。结论氪激光损伤可以创建BN大鼠脉络膜新生血管模型 ,成模时间短 ,持续时间长 ,成模率高。

Objective To evaluate the feasibility of krypton laser-induced choroidal neovascularization (CNV) model in the Brown Norway rats in order to establish the foundation for studying the mechanism of CNV and for the development of treatment for CNV. Methods Experimental eyes in 33 rats were received a series of 10 krypton red laser (647 nm) lesions per eye (360 mW, 50 μm, 0.05 s). Fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed, then the rats were sacrificed immediately, the eyes were enucleated and processed for histopathologic examination and transmission electron microscopy on days 3, 7, 14, 21, 28 and 56. Results CNV was firstly appeared on day 7 after photocoagulation, reaching the peak on day 21. The incidence of CNV was 76.0%. Disciform leakage staining appeared in the FFA. ICGA showed that the disciform area was filled with CNV. CNV was ascertained by light microscopy and electron microscopy. The thickness of laser-induced CNV was increased from day 7 to day 21 ( P <0.01) and no significant progress occurred after day 21 ( P >0.05). Conclusions The present studies demonstrated that krypton laser photocoagulation could be used to produce choroidal neovascularization experimental model in the Brown Norway rat. CNV can be induced rapidly by the method, persists for a long period and at a high successful rate.