FREQUENCY-DEPENDENT ALTERATION OF ENOLASE ACTIVITY BY ELF FIELDS

Frequency-dependent effects of electromagnetic radiation have been rep orted 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, cont aining the mammalian neuron-specific enolase (NSE) gene, was used as t he biological material. Results showed the existence of a ''window eff ect'', i.e. an alteration of enolase activity, at specific ELF frequen cies flanked only by non-effective frequencies. Ten different ELF freq uencies 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, alter ation 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 resu lts.