Effects of exposure of CHO-K1 cells to a 10-T static magnetic field.
OBJECTIVE
To evaluate whether exposure to strong static magnetic fields (SMFs), of up to 10 T, affects the growth and cycle distribution of and the micronucleus formation in monolayered Chinese hamster ovary CHO-K1 cells.


METHODS
The authors developed a system to expose cultured cells to strong SMFs immediately after the cells are seeded. Cell growth rate was evaluated according to cell number count. Cell cycle distribution experiments were performed by using flow cytometric analysis. In these experiments, the cells were exposed to SMFs for up to 4 days. The frequency of micronucleus formation with only SMF exposure at x-ray irradiation was analyzed at microscopic observation.


RESULTS
Long-term exposure to a 10-T SMF for up to 4 days did not affect cell growth rate or cell cycle distribution. Exposure to SMFs alone did not affect micronucleus frequency. In x-ray-irradiated cells, exposure to a 1-T SMF did not affect micronucleus frequency, but exposure to a 10-T SMF resulted in a significant (P <.05) increase in micronucleus frequency.


CONCLUSIONS
Strong (10-T) SMFs have no effect on cell growth, cell cycle distribution, or micronucleus frequency, but they may cause an increase in the micronucleus formation induced by 4-Gy x rays.
Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Japan.
Takehisa
T
Nakahara
Hiroko
H
Yaguchi
Masami
M
Yoshida
Junji
J
Miyakoshi
D000818:Animals; D016466:CHO Cells / Q000528:radiation effects*; D002453:Cell Cycle / Q000528:radiation effects; D006224:Cricetinae; D004574:Electromagnetic Fields; D048629:Micronuclei, Chromosome-Defective / Q000528:radiation effects; D008870:Microtubules / Q000528:radiation effects