Abstract
[Introduction] In cases of high-dose radiation exposure, one of the first priorities is to reduce and recover from radiation damage to high-reproducibility tissue, such as the hematopoietic system, intestinal mucosa, and skin. Medications can be used for primary care because hematopoietic stem cell transplant is not appropriate for use in the case of mass casualties with respect to timely treatment. However, almost all the drugs/growth factors shown to be effective in this regard in the past are not prescription drugs in Japan. There are problems with respect to standing and emergency in prompt response; therefore, appropriate countermeasures based on prescription drugs are required. In this study, appropriate therapeutic strategies for high-dose radiation casualties, especially with respect to damage to the hematopoietic system and alimentary canal, were studied using a combination of prescription drugs in a mouse model.
[Materials and Methods] Eight-week-old female C57BL/6J jcl mice were exposed to 7 Gy total body irradiation by using a 137Cs gamma source, and test drugs were given after irradiation. Recombinant human EPO, G-CSF, Nplate and nandrolone decanoate (ND) were used as test drugs. On day 30 after irradiation, survival mice of body weight, peripheral blood cells, bone marrow cells, hematopoietic progenitors, and cell surface antigens were analyzed.
[Results and Discussion] Approximately 10% of irradiated mice survived for 27 days, but all the mice died at 30 days. Of the mice that were administered EPO+G-CSF+ND or EPO+G-CSF+ND+Nplate for 3 or 5 days, 40-50% survived for 30 days. However, no significant differences were observed between the value of the parameters evaluated for irradiated mice and control. These results show that an appropriate combination of prescription drugs may help treat individuals exposed to high-dose radiation.
