INTENSITY DEPENDENCE OF ENOLASE ACTIVITY BY MODULATED RADIOFREQUENCY RADIATION

Electromagnetic radiation (EMR) effects on calcium ion (Ca2+) efflux and acetylcholinesterase (AChE) activity in neuroblastoma cells have been studied for several years. Enhanced Ca2+ efflux and AChE activities occur at certain power density regions separated by other power density regions in which no effect is observed. AChE is generally membrane-bound. Ca2+ ions exist both as extracellular and intracellular components that pass through the membrane to maintain the cellular physiological balance. In this study, observations are reported of EMR effects on a cytoplasmic biochemical parameter, activity of total enolase, a well-known enzyme in the glycolytic pathway of cells that is not membrane-bound. Two neuroblastoma cell lines - a human line IMR-32 and a rodent hybrid line NG-108 - were exposed for 30 min to 147 MHz radiation, amplitude-modulated (AM) at 16 Hz (80%). The power intensities used had specific absorption rate (SAR) values of 0.001, 0.01, 0.02, 0.05, 0.07, 0.08, 0.09, 0.10 and 0.50 mW/g. At SAR 0.05 mW/g, there was significant enhancement in all three biochemical parameters (AChE, Ca2+ and enolase). All three biochemical activities were significantly depressed at SAR 0.01 mW/g. Enolase activity was also significantly depressed at SAR 0.08 mW/g using the NG-108 neuroblastoma cell line. Almost no effects were observed in any of these parameters at the higher intensities of 0.1 and 0.5 mW/g. The intensity dependences induced by EMR were similar, although not identical, in all three biochemical parameters tested.