title: [Absorption of iodofolic acids by the cells of malignant tumors].
abstract: The uptake of 125-iodine labeled 3' iodofolic acid (I*F) and 3' iodo, 5 formyl tetrahydrofolic acid (I*FT) by the cells HeLa, ECV, L-41, human glioma, and rat glioma was studied. Human Embrionic Lung Fibroblasts (HELF) were taken for comparison as healthy cells. It was shown for *IF that its long-term uptake by cells L-41 and ECV is hundreds oftimes higher than those of HELF cells. The short-term uptake phase was studied for *IFT uptake. The dissociation constant was determined for a complex formed by *IFT and an acceptor in the HeLa cells, which is supposed to cause concentrative uptake of *IFT in cells. The dissociation constants of this acceptor complexes with folic acid, 3' iodofolic acid and 3',5'-diiodofolic acid were determined by competition with I*FT. The distribution ratio of *IF and *IFT in tissues of different organs of healthy mice and rats and rats with a sarcoma grafted on his thigh and glioma grafted into the brain was studied. As was shown there are large differences in the concentration of *IF and *IFT in the tumor and in the healthy tissue, *IF concentration in thigh muscle of healthy being 5 times lower than those in tumor grafted to the thigh, and *IFT concentration in healthy brain being 10 times lower than in brain tumor.
authors.forename: N V
authors.initials: NV
authors.lastname: Soroka
authors.forename: M V
authors.initials: MV
authors.lastname: Filatov
authors.forename: V G
authors.initials: VG
authors.lastname: Korolev
authors.forename: G A
authors.initials: GA
authors.lastname: Bagiian
authors.forename: K D
authors.initials: KD
authors.lastname: Aplin
authors.forename: G G
authors.initials: GG
authors.lastname: Gridasov
mesh_terms: D000042:Absorption; D000818:Animals; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism; D005492:Folic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D007455:Iodine / Q000737:chemistry / Q000494:pharmacology; D007457:Iodine Radioisotopes / Q000008:administration & dosage; D008297:Male; D051379:Mice; D009374:Neoplasms, Experimental / Q000737:chemistry / Q000378:metabolism; D011859:Radiography; D051381:Rats; D018235:Smooth Muscle Tumor / Q000737:chemistry; D014018:Tissue Distribution
chemical_list: D007457:Iodine Radioisotopes; D005492:Folic Acid; D007455:Iodine