Frequency-dependent alteration of enolase activity by ELF fields

Abstract

Frequency-dependent effects of electromagnetic radiation have been reported at microwave and other r.f. ranges. The present study determined frequency-dependent alteration of enolase (EC 4.2.1.11, a cytoplasmic enzyme in the glycolytic pathway) activity by extremely low frequency (ELF) electric ( E), magnetic ( H) and combined electric and magnetic ( E & H) fields in a Crawford cell exposure system. A clone, pNGE7, containing the mammalian neuron-specific enolase (NSE) gene, was used as the biological material. Results showed the existence of a “window effect”, i.e. an alteration of enolase activity, at specific ELF frequencies flanked only by non-effective frequencies. Ten different ELF frequencies from 10 to 72 Hz were used. Enolase activity was reduced when cells were exposed to a 60 Hz E field. In combined E & H fields, alteration of enolase activity was decreased at 15, 55, 65 and 72 Hz. These data show a field-specific effect of ELF. We have also observed that some physical factors, such as slight vibration of the cells which may occur while the cells are being exposed, can show false negative results.