光动力学疗法对肿瘤微血管形态学的影响

Morphological Change of Tumor Microvasculature Following Photodynamic Therapy(PDT)

以大鼠Ｗａｌｋｅｒ－２５６肿瘤为模型，通过光镜、电镜观察光动力学疗法（ＰＤＴ）后不同时期肿瘤微血管系统组织形态学变化及肿瘤杀伤情况。实验发现，ＰＤＴ后肿瘤微血管系统呈进行性损害，微血管损伤后的缺血缺氧可能是导致肿瘤坏死的重要机制之一。

In this study,the effect Of PDT on tumor microvasculature was studied by light and electron microscope.Walker 256 tumor as a model test,implanted subcutaneously in rats,was exposed to wave length 630nm,output power 360mW the energy density 200J/cm2 after 24 hours of PSD-007 injection with dose of 15mg/kg.Then,the animals were killed and tumors were removed at time 0,l,2,6,12,24 hours after treatment.The tumors with PDT displayed Pro- gressive injury to both tumor microvasculature and cells.Pathological changes,such as swelling and vascuolization of mitochondria in endothelial cells, were seen immediately following PDT.After PDT,the injury of endothelial cells became more severe and the tumor cells Presented microthrombosis,diffuse hemorrhage,and necrosis.The result indicates that disruption of tumor microvasculature may be an important mechanism for tumor necrosis with PDT.