title: Effect of photodynamic therapy on blood flow in normal and tumor vessels.
abstract: The aim of this series of experiments was to determine the dynamic blood flow changes that occur in normal and neoplastic tissues during photodynamic therapy. Mice bearing SMT-F tumors and rats with transplanted chondrosarcomas were injected with graded doses of dihematoporphyrin ether. Studies of changes in single-vessel and whole-tumor blood flow were carried out with 630 nm light activation. A helium neon laser Doppler velocimeter was used to stimulate dihematoporphyrin ether, as well as to measure changes in flow velocity in both single-vessel and whole-tumor models. There was a reduction of flow velocity in all vessels and tumors in animals injected with 1 to 40 mg/kg dihematoporphyrin ether intraperitoneally. The extent of flow reduction was related to drug dose administered. Decreases in blood flow began within 10 seconds of light stimulation and were maximal within 5 minutes. Both normal and tumor vessels responded similarly. We conclude that photodynamic therapy leads to significant microcirculatory changes that may be pertinent to the mechanism of tumor necrosis.
authors.affiliation: Department of Surgery, James Graham Brown Cancer Center, University of Louisville, School of Medicine 40292.
authors.forename: T J
authors.initials: TJ
authors.lastname: Wieman
authors.forename: T S
authors.initials: TS
authors.lastname: Mang
authors.forename: V H
authors.initials: VH
authors.lastname: Fingar
authors.forename: T G
authors.initials: TG
authors.lastname: Hill
authors.forename: M W
authors.initials: MW
authors.lastname: Reed
authors.forename: T S
authors.initials: TS
authors.lastname: Corey
authors.forename: V Q
authors.initials: VQ
authors.lastname: Nguyen
authors.forename: E R
authors.initials: ER
authors.lastname: Render
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001158:Arteries / Q000187:drug effects / Q000502:physiology / Q000503:physiopathology; D002813:Chondrosarcoma / Q000098:blood supply / Q000188:drug therapy*; D017323:Dihematoporphyrin Ether; D005260:Female; D006415:Hematoporphyrins / Q000627:therapeutic use*; D008297:Male; D008325:Mammary Neoplasms, Experimental / Q000098:blood supply / Q000188:drug therapy*; D051379:Mice; D008811:Mice, Inbred DBA; D010778:Photochemotherapy; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D012039:Regional Blood Flow / Q000187:drug effects; D012867:Skin / Q000098:blood supply*
chemical_list: D000970:Antineoplastic Agents; D006415:Hematoporphyrins; D017323:Dihematoporphyrin Ether