Abstract
Radiation induced acute changes of mouse hematopoietic functions and its recovery were studied in different LET of heavy ions, carbon (13, 30 keV/mm), neon (32, 55 keV/mm), silicon (56 keV/mm), argon (85 keV/mm), iron (200 keV/mm). After whole body irradiations up to 3 Gy, the subsequent hematopoietic parameters were followed by the blood analysis for 8 days. All hematological functions, spleen weight, granulocyte-monocyte colony forming unit (GM-CFU) in bone marrow and spleen indicated dose dependent reduction within 2 days after the irradiation and followed by a slow recovery. GM-CFU in spleen showed the highest sensitivity to all particles, showing a large reduction down to less than 1% of the control at 3 Gy irradiation. Of the particle exposed Si (55 keV/mm) induced the largest reduction and the slowest recovery, whereas Fe (200 keV/mm) indicated the least reduction and the fastest recovery. The results suggested a strong LET dependency of the hematopoietic progenitor cells which may have a RBE maxima less than 100 keV/mm. [J Radiat Res 44:417 (2003)]
