THE ION PARAMETRIC RESONANCE MODEL PREDICTS MAGNETIC-FIELD PARAMETERS THAT AFFECT NERVE-CELLS

An ion parametric resonance (IPR) model recently developed by Blanchard and Blackman predicts distinct magnetic field interactions with biological systems based on a selective relation among four factors: the flux density of the static magnetic field, the frequency and flux density (B-ac) of the parallel ac magnetic field, and the charge to-mass ratio of ions of biological relevance, To test this model, PC-12 cells stimulated by nerve growth factor to produce neurites were exposed for 23 h in a 5% CO2 incubator using a multiple coil exposure system to produce 45 Hz ac and de (366 mG parallel to ac; less than 2 mG perpendicular to ac) magnetic fields, Our earlier work showed a cycle of inhibition/no inhibition of neurite outgrowth consistent with the IPR model predictions for B-ac exposures between 0 and 468 mG rms, The work described here tests neurite outgrowth over a broader range of B-ac (233-1416 mG rms), The experimental results remain consistent with earlier results, and with IPR model predictions of a second cycle of inhibition, return to control values, followed by a third cycle of inhibition of neurite outgrowth, These responses support the fundamental relationships predicted by the IPR model, The results have broad significance for biology.