INCREASED DEXAMETHASONE-INDUCED APOPTOSIS OF THYMOCYTES FROM MICE EXPOSED TO LONG-TERM EXTREMELY-LOW-FREQUENCY MAGNETIC-FIELDS

To address the effect of extremely low frequency electromagnetic field s on programmed cell death we assessed both the spontaneous and dexame thasone (Dex)-induced apoptosis of thymocytes and spleen cells from mi ce submitted to a long-term continuous exposure of a 0.4-1.0 mu T 60 H Z magnetic field or an 8-20 mu T direct current (DC) magnetic field. D ex-induced apoptosis but not spontaneous apoptosis was substantially i ncreased in thymocytes from 0.4 to 1.0 mu T 60 Hz field-exposed animal s. Spontaneous apoptosis and Dex-induced apoptosis of spleen cells wer e not affected by the 0.4-1.0 mu T 60 Hz field exposure. In addition, spontaneous apoptosis and Dex-induced apoptosis of thymocytes and sple en cells from mice exposed to an 8-20 mu T DC field were similar to th e controls. These findings represent the first demonstration that thym ocytes from mice exposed to a long-term 0.4-1.0 mu T 60 Hz field may s how abnormal response to Dex apoptotic stimuli. (C) 1998 Wiley-Liss, I nc.