Effects of ELF (1–120 Hz) and modulated (50 Hz) RF fields on the efflux of calcium ions from brain tissue in vitro

✍ Scribed by C. F. Blackman; S. G. Benane; D. E. House; W. T. Joines

• Publisher: John Wiley and Sons
• Year: 1985
• Tongue: English
• Weight: 660 KB
• Volume: 6
• Category: Article
• ISSN: 0197-8462
• DOI: 10.1002/bem.2250060102

✦ Synopsis

We have previously shown that 16-H~. sinusoidal electromagnetic fields can cause enhanced efflux of calcium ions from chick brain tissue, in vitro, in two intensity regions centered on 6 and 40 V,~,/m. Alternatively, I-Hz and 30-Hz fields at 40 V,.,/m did not cause enhanced efflux. We now demonstrate that although there is no enhanced efflux associated with a 42-Hz field at 30, 40, 50, or 60 Vp-,/m, a 45-Hz field causes enhanced efflux in an intensity range around 40 V,-,,/m that is essentially identical to the response observed for 16-Hz fields. Fields at 50 Hz induce enhanced efflux in a narrower intensity region between 45 and 50 Vp.,/m, while radiofrequency carrier waves, amplitude modulated at 50 Hz, also display enhanced efflux over a narrow power density range. Electromagnetic fields at 60 Hz cause enhanced efflux only at 35 and 40 V,,/m, intensities slightly lower than those that are effective at 50 Hz. Finally, exposures over a series of frequencies at 42.5 V,,/m reveal two frequency regions that elicit enhanced efflux-one centered on 15 Hz, the other extending from 45 to 105 Hz.