OBJECTIVETo study the possible induction effect of exposure to 50 Hz magnetic field (MF) on clustering of cell membrane surface receptors for epidermal growth factor (EGF) and tumor necrosis factor (TNF), the starting site of signals of biological effects, and its possible intervention effect.

METHODSLung fibroblasts of Chinese hamster (CHL) were exposed to EGF, TNF, 0.4 mT 50 Hz MF, 0.4 mT noise MF, and 0.4 mT 50 Hz MF combined with 0.4 mT noise MF. Respectively, for different durations, following the treatment, EGF and TNF receptors on the cell membrane were marked by corresponding antibodies with immunohistochemical method, then observed under a confocal microscope.

RESULTSClustering of cell membrane receptors could be induced 5 min after treatment with EGF and TNF, as well as with 50 Hz MF at 0.4 mT, which reached the peak in 15 min. While noise MF with the same intensity did not induce clustering of cell membrane receptors. Superposition of noise MF with the same intensity could inhibit clustering of cell membrane receptors induced by 50 Hz MF.

CONCLUSIONClustering of EGF and TNF receptors on the cell membrane could be induced by 50 Hz MF, suggesting that membrane receptors would be one of the sites where MF signals coupled, and noise MF with the same intensity could inhibit these effects.