The Mechanism of Endotoxin-Induced Hypoferraemia

The effect of endotoxin on the processing of erythrocyte iron by reticuloendothelial cells of the liver and spleen was studied in rats using heat damaged erythrocytes labelled with ⁵⁹Fe. Endotoxin did not alter the uptake of the damaged cells but markedly inhibited the subsequent early phase of iron release from the reticuloendothelial cells. The inhibition seemed to be due to both a decreased rate of labelled haem destruction and an increased incorporation of radioiron into ferritin. Although early iron release was decreased 0–2 h after endotoxin administration, the diversion of iron into ferritin was more marked when endotoxin was given 18 h before. The block in iron release was partially overcome in animals that had been kept on an iron free diet or had been phlebotomised. In these animals the decreased rate of haem catabolism remained unaltered but less iron was diverted into ferritin.