Mechanism of Tumor Destruction Following Photodynamic Therapy With Hematoporphyrin Derivative, Chlorin, and Phthalocyanine

摘要: The effect of photodynamic therapy on the tumor microvasculature in first few hours after treatment was studied at light and electron microscopy levels. BALB/c mice with EMT-6 received ip injections hematoporphyrin derivative, chlorin, or phthalocyanine, 24 later, tumors were treated 100 J/cm2 appropriate therapeutic wavelength for each photosensitizer. Animals killed their removed time 0, 30 minutes, 1 hour, 2, 4, 6, 8, 12, 16, treatment. results indicate that all three sensitizers effects leading to rapid necrosis tissue are not result direct cell kill but secondary destruction microvasculature. observable signs occur subendothelial zone capillary wall. This zone, composed dense collagen fibers other connective elements, is destroyed phototherapy. However, ultrastructural changes seen this different compared chlorin phthalocyanine. Binding photosensitizers elements as well altered permeability transport through endothelial layer because increased intraluminal pressure may be key features destruction.