Uptake of Transferrin-Bound Iron by Rat Cells in Tissue Culture
| Autor: | T. Okigaki, M. R. Beamish, Elmer B. Brown, L. Keay |
|---|---|
| Rok vydání: | 1975 |
| Předmět: |
Reticulocytes
Time Factors Iron Cell Tissue culture Pregnancy medicine Animals Incubation Cells Cultured chemistry.chemical_classification Binding Sites biology medicine.diagnostic_test Chemistry Transferrin Embryo Hematology Embryo Mammalian In vitro Rats Ferritin medicine.anatomical_structure Liver Biochemistry biology.protein Serum iron Female |
| Zdroj: | British Journal of Haematology. 31:479-491 |
| ISSN: | 1365-2141 0007-1048 |
| DOI: | 10.1111/j.1365-2141.1975.tb00883.x |
| Popis: | Summary. The in vitro uptake of transferrin-bound iron by rat liver cells and rat embryo cells in culture, and by rat reticulocytes, was studied using labelled rat serum. The uptake of iron by rat liver cells was linear with time and showed a curvilinear relationship with the serum iron concentration. Over 40% of the cell radioactivity was found to be ferritin associated. Incubation of rat transferrin doubly labelled with 59Fe and 125l showed a difference between the uptakes of the two isotopes suggesting reflux of transferrin from the cell after iron uptake. In order to compare iron uptake from half saturated (Tf-Fe 1) and fully saturated (Tf-Fe2) transferrin, the three cell systems were each incubated in sera labelled with 55Fe at 10% saturation and with 59Fe at varying iron saturations ranging from 10% to 90%. Similar experiments were performed with sera having been randomly labelled with 55Fe and labelled with 59Fe but preincubated with reticulocytes in order to produce iron bound to non-reticulocyte orientated transferrin binding sites. The data obtained confirms the presence of a functional heterogeneity with respect to the half and fully saturated transferrin. Thus iron uptake from fully saturated transferrin was almost twice that for the half saturated molecule with rat liver cells or reticulocytes, and over three times that of the half saturated molecule with rat embryo cells. In contrast no such differences could be detected when iron uptake from serum randomly labelled with iron and serum with labelled non-reticulocyte orientated binding sites were compared. Finally, the effect of pre-incubating each of the three cell systems in unlabelled sera of varying percentage iron saturations on subsequent radio-iron uptake was studied. An inverse relationship between percentage saturation of the preincubation serum and subsequent uptake was demonstrated indicating that cellular mechanisms also influence cell iron uptake. |
| Databáze: | OpenAIRE |
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