Regulation of Plasma Ferritin by the Isolated Perfused Rat Liver

S ummary . The isolated perfused rat liver has been used to investigate the regulation of plasma ferritin in normal, iron-deficient and iron-overloaded states. Both ¹²⁵I-labelled and non-labelled rat liver ferritins were rapidly cleared from the perfusion circuit with a half-life of approximately 30 min. Perfusion of livers from normal, iron-loaded or iron-deficient rats with blood obtained from normal, iron-loaded or iron-deficient rats showed that the liver takes up plasma ferritin, and releases ferritin into the perfusate to achieve a perfusate ferritin level appropriate to the iron stores of the animal from which the liver was taken. It is concluded that the liver is capable of both uptake and release of ferritin and that within the liver there resides a mechanism which maintains circulating ferritin concentrations at a level appropriate to body iron stores.