Relation between polyporphyrin distribution and blood brain barrier changes in the rat glioma model.
Photofrin (a polyporphyrin mixture) distribution in a rat glioma model was studied in relation to changes in the blood brain barrier (BBB). At selected intervals after intraperitoneal injection of Photofrin, the concentration of polyporphyrins (PP) and Evans Blue Dye, an indicator of BBB permeability, were determined for tumor, brain adjacent to tumor (BAT), and normal brain tissue. Contrary to earlier reports of maximal accumulation at 4-24 hours, tumor levels of PP increased throughout the 96 hour measurement period. During the early stages of tumor development, PP uptake by tumor appeared to be less correlated to BBB disruption. We conclude that passive diffusion through an incompetent BBB does not completely explain PP accumulation in tumor tissue.
Ji
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Division of Neurological Surgery, University of North Carolina, Chapel Hill 27599-7060.
Walstad
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DL
Brown
J T
JT
Powers
S K
SK
D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D001932:Brain Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D002460:Cell Line; D002463:Cell Membrane Permeability / Q000187:drug effects; D004195:Disease Models, Animal; D004354:Drug Screening Assays, Antitumor; D005070:Evans Blue; D005910:Glioma / Q000188:drug therapy / Q000378:metabolism*; D017324:Hematoporphyrin Derivative; D006415:Hematoporphyrins / Q000493:pharmacokinetics* / Q000627:therapeutic use; D008297:Male; D009368:Neoplasm Transplantation; D010778:Photochemotherapy; D011838:Radiation-Sensitizing Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use; D051381:Rats; D011919:Rats, Inbred Strains; D014018:Tissue Distribution
D006415:Hematoporphyrins; D011838:Radiation-Sensitizing Agents; D005070:Evans Blue; D017324:Hematoporphyrin Derivative