[Biological effects of static gradient magnetic field on cultured mammalian cells and combined effects with 60Co gamma-rays].

The biological effects of a static gradient magnetic field and its combined effects with ionizing radiation on FM3A cultured cells were investigated. The magnetic strength of the center of the field was 5.8 x 10(-2) T esla, the mean gradient of the magnetic filed was 0.6 T esla/m. The magnetic field influenced cell cycle. The relative amount of cultured cells in G1 phase decreased for eight hours after exposure. The growth rate of the cells was slowed by about 5%. Following exposure to the magnetic field, the survival rate of cells decreased to about 20% less than that of the non-exposed control. The combined effect of 60Co irradiation with exposure to the magnetic field showed a greater effect than a simple additive one. The combined effect was influenced by the interval between 60Co irradiation and exposure to the magnetic field. The biological effects of the magnetic field may be related to age-dependent cellular damage in the cell cycle, blockage of cell progression in the cell cycle, and increased repair from radiation damage.