激光诱导有色大鼠脉络膜新生血管的形态学观察

Characteristics of choroidal neovascularization induced by laser in pigmented rats

目的观察激光诱导有色大鼠脉络膜新生血管（choroidal neovascularization，CNV）的形态学变化，为CNV机制及治疗的研究提供科学的平台和有效客观的评价方法。方法雄性BN大鼠52只（104眼），每只鼠一只眼作为实验眼，另一只眼为对照眼。532nm倍频激光光凝，激光功率、光斑直径和曝光时间分别为140mW、75μm和100ms，每眼光凝8-10点。光凝后1d、3d、7d、14d、21d、28d、56d及110d行荧光素眼底血管造影和吲哚青绿血管造影检查后处死动物，摘除眼球制作标本进行组织病理学观察，并于光凝后3d、7d和56d行透射电镜观察。结果光凝后3d光斑处有内皮细胞的增生，CNV于7d开始形成，14d达高峰，造模成功率为75％．荧光素眼底血管造影显示，造影早期可清晰判断CNV形态，晚期典型圆盘状荧光素渗漏。吲哚青绿血管造影检查可见CNV充盈。光镜和电镜下均可见口Ⅳ形成。CNV厚度自光凝后7～14d逐渐增加，之后变化不显著。Ⅷ因子标记的CNV血管密度7～14d逐渐增加，之后变化不显著，56d后逐渐减低。结论激光诱导有色大鼠CNV模型，成模时间短，成模率高，观察时间长，是一种较为理想的实验模型。【眼科新进展2006；2613）：161—166]

Objective To evaluate the feasibility of laser-induced choroidal neovascularization（CNV）model in the pigmented rats in order to establish the foundation for studying the mechanism of CNV and for the assessment of new therapeutic approaches. Methods Experimental eyes in 48 rats were received a series of 8-10 532 nm laser lesions per eye（140 mW,75μm, 100 ms）. Fundus fluorescein angiography and indocyanine green angiography （ICGA）were performed,then the rats were sacrificed immediately, the eyes were enucleated and processed for htstopathologte examination and transmission electron microscopy on day 1,3,7,14,21,28,56 and 110,Results CNV was firstly appeared on day 7 after photocoagulation, reaching the peak on day 14. The incidence of CNV was 75.0%. Early phase fluorescein angiography showed a reticular neovascular network; late phase angiography showed active disciform leakage. Morphology visualization was clearest in the early angiogram phase. ICGA showed disciform dye leakage in the late phase. CNV was ascertained by light microscopy and electron microscopy. The thickness of laser-induced CNV was increased from day 7 to day 14 （P 〈0.05） and no significant progress occured after day 14 （P〉 0.05）. Factor Ⅷ labeled CNV vascular density was increased from day 7 to day 14（P〈0.05）, no significant progress occured after day 14（P〉0.05） and diminished gradually after day 56. Conclusiono CNV in the pigmented rat was characterized by rapid development of neovascular membrane and proliferation of retinal pigment epithelium in the subretinal space, persistance for a long period and a high successful rate. This model may be useful for tn vtvo studies of choroidal angiogenesis and its modulation via drug therapy. [Rec Adv Ophthalmol 2006;26（3）：161-166]