Difference in the Mechanism of Radioprotection between Carbon Particles and Bacterial Endotoxin

Abstract

Difference between carbon particles and bacterial endotoxin in their modes of radioprotection was examined. Radioprotection by bacterial endotoxin was carried out without corresponding enhancement of the haemopoietic stem cell survival, whereas the increased survival of the carbon treated animals was in good accordance with the enhancement of the survival of the haemopoietic stem cells in the treated animals. Radioprotection by bacterial endotoxin, therefore, seems to be due to the enhanced induction of the differentiation of the stem cells to recruit functioning blood cells.