Angiogenesis Induced by Photodynamic Therapy in Normal Rat Brain¶

• DOI: 10.1562/2003-11-19-rc.1
• Publication Date: 2004-06-24T17:44:39Z
• Authors: Feng Jiang; Zheng Gang Zhang; Mark Katakowski; Adam M Robin; Michelle Faber; Fan Zhang; Michael Chopp
• Keywords: Immunostaining

Angiogenesis promotes tumor growth and invasiveness in brain. Because brain injury often induces expression of angiogenic-promoting molecules, we hypothesize that oxidative insult induced by photodynamic therapy (PDT) could lead to an endogenous angiogenic response, possibly diminishing the efficacy PDT treatment tumors. Therefore, sought establish whether response within nontumored using Photofrin as a sensitizer at optical dose 140 J/cm2 was performed on normal rat (n = 30). Animals were sacrificed 24 h, 1, 2, 3 6 weeks after treatment. Fluorescein isothiocyanatedextran perfusion performed, brains fixed for immunohistological study. Immunostaining revealed vascular endothelial factor (VEGF) increased PDT-treated hemisphere 1 week remained elevated weeks. Three-dimensional morphologic analysis vasculature contralateral demonstrated PDT-induced angiogenesis, indicated significant increase vessel connectivity (P < 0.001) concomitant with decreased 0.05) mean segment length compared vessels hemisphere. Volumetric measurement regions indicate neovascular expansion continued 4 PDT. These data demonstrate VEGF neovascularization angiogenesis tumor, antagonizing this may present practical means enhance