Uptake of iron from transferrin by isolated hepatocytes.
Isolated rat hepatocytes containing 0.56-1.79 micrograms iron/10(6) cells and with an intracellular ATP concentration of 3-4 mM, accumulate iron from transferrin linearly with time for at least 3 h. At 37 degrees C the rate of uptake amounts to 0.3-0.7 pmol/mg cell protein per min. The uptake reaches a saturation level of 21-40 pmol/mg cell protein per h at 2.2 microM iron. At 5 degrees C the uptake does not increase over the time of incubation. Uptake of iron, but not binding of transferrin is increased 4-5-fold at oxygen concentrations 10-20 microM. At oxygen concentrations beyond these limits iron uptake is decreased. Iron taken up at low oxygen concentrations can be chelated by bathophenanthroline and bathophenanthroline disulphonate , but only if the chelators are present during the uptake experiments. The results suggest that iron uptake from transferrin by hepatocytes in suspension involves reductive removal of iron.
D000255:Adenosine Triphosphate / Q000378:metabolism; D000332:Aerobiosis; D000818:Animals; D001692:Biological Transport; D002470:Cell Survival; D002614:Chelating Agents / Q000494:pharmacology; D004705:Endocytosis; D006801:Humans; D066298:In Vitro Techniques; D007501:Iron / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000378:metabolism; D011990:Receptors, Transferrin; D014168:Transferrin / Q000378:metabolism*
D002614:Chelating Agents; D011956:Receptors, Cell Surface; D011990:Receptors, Transferrin; D014168:Transferrin; D000255:Adenosine Triphosphate; D007501:Iron