叶绿素光敏剂对鸡冠微血管损伤机理探讨

An experiment study of injury mechanism of vascular structure in chicken comb following CPD4 sensitized photodynamic therapy

目的：观察鸡冠微血管在叶绿素光敏剂光动力治疗后的超微结构变化。方法：２４只动物随机分成对照组和治疗组，光动力治疗组治疗参数为：给药至照光间隔时间１０ｍｉｎ，光敏剂剂量每千克体重给１０ｍｇ，功率密度１５０ｍＷ／ｃｍ２，能量密度９０Ｊ／ｃｍ２，治疗光源为主发射峰位于６５０ｎｍ的红光。结果：透射电镜观察显示红细胞破坏，形态不规则，内皮细胞肿胀致血管腔变窄，胞膜破裂，线粒体肿胀、空泡化，内质网扩张，核染色质聚积或边集、核溶解，部分区域可见内皮细胞脱落，血管基膜及管周胶原纤维暴露，血栓形成。结论：内皮细胞是光动力损伤的主要靶部位，光动力效应产生的单态氧或氧自由基对内皮细胞造成直接光毒损伤，血管内层损伤导致凝血因子释放，血栓形成引起的缺氧加重、加速了血管组织的损伤。

Objective: To observe the ultrastructure changes of chicken comb following chlorophyll derivative IV(CPD4) sensitized photodynamic therapy (PDT).5HZMethods: Chicken combs were treated with red light at 650 nm of main emitting peak,150 mW/cm2 of power density and 90 J/cm2 of energy density 10 min after injection of CPD4 at the dose of 10 mg/kg in 12 chickens.Another 3 chickens were used as the control .Then the combs were observed with transmission electronic microscope. Results: Swelling and irregular morphology of erythrocytes and endothelial cells(EC) were observed.Loss of cell membrane intergrity,swelling and vacuolization of mitochondria,expansion of endoplasmic reticulum ,dissolution of nucleus,loss of EC,exposure of blood vessel lamina and thrombus were found in the treated chicken combs. Conclusion: EC may be the main target of PDT.Singlet oxygen or oxygen radicals, clotting factor induced by PDT,vascular occlusion and hypoxia may be related to the damage of vascular structure.