竹红菌乙素对脉络膜毛细血管光动力效应的初步观察

Experimental Study of Photodynamic Effects using Hypocrellin B on the Choriocapillaris in Rabbits

目的:观察竹红菌乙素 光动力治疗(HB PDT)对青紫蓝兔脉络膜毛细血管的生物学效应的特点,探讨HB PDT治疗脉络膜新生血管以及绿光作为PDT治疗的光源的研究前景。方法:使用光纤连接532nm激光器和裂隙灯显微镜,选用青紫兰兔2.5kg～3.5kg,全麻生效后,耳缘静脉内注射HB1.0mg kg,532nm光线作为光源激发光敏剂,眼底光斑功率密度300mW cm2,能量密度30J cm2,注射药物后立刻照光,光斑直径2000μm,6例,于PDT后1d、7d、28d观察视网膜,荧光眼底造影、光学显微镜和电子显微镜观察照光部位视网膜和脉络膜的生物学效应。结果:PDT后1d,照光区域脉络膜毛细血管管腔内形成光动力血栓,视网膜的损伤以外层为主,内层没有明显改变。第7d脉络膜毛细血管内皮细胞损伤加重,脉络膜大血管无明显改变,第28d后在原来毛细血管的部位出现纤维组织,玻璃膜增厚;照光区域的RPE细胞出现修复、增殖。结论:PDT后第1d至第7d靶组织的生物学效应和非靶组织的非选择性开始出现并不断增强,第28d后逐渐以纤维组织恢复。HB PDT治疗AMD或其它以脉络膜新生血管为特点的眼底疾病,有进一步研究价值。

Objectives: Performing the HB-PDT on the rabbit's fundus to observe the biological effects on the irradiated retinal and choroidal area to investigate whether or not the HB-PDT is safe and effective in treating the choroidal neovascularizaton (CNV) and the green laser can be used as the light source during PDT. Methods: After linking the 532nm laser and split microscope, the samples were irradiated soon after the injection of HB using 532 nm laser as light source with power density 300 mW/cm^2, energy fluence 30 J/cm^2. The cases were examined by fundus photography, fluorescein angiography and histology to probe the biological effect in the irradiated area at the 1^(st), 7^(th) and 28^(th) day after PDT.Results: There was photodynamic thrombum in the choriocapillaris lumen with damage to the outer retina and intact inner retina on the 1st day after HB-PDT. The biological effect on the retina and choriocapallaris become serious since the 7^(th) day after HB-PDT. The damaged choriocapallaris and retina were mended by fibrous tissue until 28^(th) day. Conclusions: The biological effect on the retina and choriocapallaris become obvious after PDT and it could still be seen and went through until the 28^(th) day with the fibrous recovery finally. HB-PDT can be used to treat disease characterized by choroidal neovascularization, such as AMD.