Cellular Sites of Hepatic Ferritin Activation and Inactivation

¹ From the Department of Medicine, Cornell University Medical College and the New York Hospital, New York City

Studies with viable reticulo-endothelial (RE) and parenchymal cells separated from the liver show that the parenchymal cells contain most of the liver ferritin. This ferritin is vasoinert, and anaerobic incubation of the parenchymal cells does not release it in vasoactive form. Aerobic parenchymal cells readily inactivate exogenous vasoactive ferritin. Parenchymal cells isolated from the liver of normal rats subjected to traumatic shock contain vasoactive ferritin and have lost their ferritin inactivating capacity, whereas those from resistant rats subjected to the same trauma contain only vasoinert ferritin and are still able to inactivate added ferritin. On the other hand, RE cells contain smaller amounts of vasoinert ferritin but readily release it in vasoactive form on anaerobic incubation. RE cells are not able to inactivate exogenous ferritin. When a small amount of a vasoinert, clear extract, prepared from homogenized RE cells, is added to parenchymal cells during anaerobic incubation, the parenchymal cells release their ferritin in vasoactive form. The ‘activator’ obtained from the RE cells has not been identified.