Abstract
We investigated the mechanism underlying the radioadaptive response that rescues low-dose preirradiated mice from hematopoietic failure after challenge irradiation and found that myeloid cells were rapidly recovered following the challenge irradiation in the bone marrow of low-dose-preirradiated mice. Cytokine profiles were also indicated that the concentrations of growth factors for myelopoiesis after the challenge irradiation were considerably increased by low-dose preirradiation. Especially, granurocyte colony stimulating factor, G-CSF, was significantly upregulated immediately after challenge irradiation in the low-dose-preirradiated mice. Then we evaluated the effect of administration of G-CSF after challenge irradiation on modifying the survival rate of mice without low-dose preirradiation in this study.