Effects of 900-MHz microwave radiation on gamma-ray-induced damage to mouse hematopoietic system

Exposure of humans simultaneously to microwave and gamma-ray irradiation may be a commonly encountered phenomenon. In a previous study data showed that low-dose microwave radiation increased the survival rate of mice irradiated with 8Gy gamma-ray; however, the mechanisms underlying these findings remain unclear. Consequently, studies were undertaken to examine the effects of microwave exposure on hematopoietic system adversely altered by gamma-ray irradiation in mice. Preexposure to low-dose microwaves attenuated the damage produced by gamma-ray irradiation as evidenced by less severe pathological alterations in bone marrow and spleen. The protective effects of microwaves were postulated to be due to up-expression of some hematopoietic growth factors, stimulation of proliferation of the granulocyte-macrophages in bone marrow, and inhibition of the gamma-ray induced suppression of hematopoietic stem cells/hematopoietic progenitor cells. Data thus indicate that prior exposure to microwaves may be beneficial in providing protection against injuries produced by gamma-ray on the hematopoietic system in mice.