Enhanced NOR-1 gene expression by exposure of Chinese hamster cells to high-density 50 Hz magnetic fields.
Enhanced expression of neuron derived orphan receptor (NOR-1) gene was observed by exposure of Chinese hamster ovary K1 (CHO-K1) cells to an extremely low frequency magnetic field (ELFMF) of 50 Hz at 400 mT, but not at 5 mT. The enhanced expression, reaching the maximum at 6 h, was transient and reduced to the control level after exposure to 400 mT ELFMF for 24 h. The NOR-1 expression induced by treatment with forskolin and TPA was further enhanced by the simultaneous treatment with 400 mT ELFMF, in which the maximum response was at 3 h. The NOR-1 expression by these treatments was induced more earlier than that by 400 mT ELFMF alone. When cells were treated with an inhibitor of the protein kinase C (calphostin C or crocetin) and Ca2+ entry blockers (nifedipin and dantrolen) during the 400 mT ELFMF exposure, the enhanced NOR-1 expression was not observed. Exposure of CHO-K1 cells to the high-density 400 mT ELFMF may affect the signal transduction in the cells, resulting in the enhanced NOR-1 gene expression.
Miyakoshi
J
J
Department of Radiation Genetics, Faculty of Medicine, Kyoto University, Japan.
Tsukada
T
T
Tachiiri
S
S
Bandoh
S
S
Yamaguchi
K
K
Takebe
H
H
D000818:Animals; D016466:CHO Cells / Q000502:physiology*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002338:Carotenoids / Q000494:pharmacology; D005576:Colforsin / Q000494:pharmacology; D006224:Cricetinae; D004268:DNA-Binding Proteins / Q000235:genetics*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D008280:Magnetics; D009281:Naphthalenes / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000235:genetics*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D012333:RNA, Messenger / Q000032:analysis; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014801:Vitamin A / Q000031:analogs & derivatives
D002121:Calcium Channel Blockers; D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors; D009281:Naphthalenes; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; C487773:trans-sodium crocetinate; D014801:Vitamin A; D005576:Colforsin; D002338:Carotenoids; D011493:Protein Kinase C; C058819:calphostin C; D013755:Tetradecanoylphorbol Acetate