Model analysis of the effect of modulated electromagnetic fields with various parameters of modulating signals in cells

A theoretical analysis of the dependence of cell response to modulated electromagnetic fields on the parameters of modulating signals was performed on the basis of the model for calcium-dependent membrane-associated intracellular signaling systems. Expressed amplitude-frequency "windows" in the response of the nonlinear system to external influence were shown to depend on the effective time during which the amplitude of the influencing signal exceeded some threshold value, which is determined by the properties of the system. The presence of negative values in the influencing signal, i.e. the variations in the rate of some process around the inherent value, played an important role for the effect characteristics. The response of the nonlinear system to external influence strongly depended on the waveform of the modulating signal which is determined not only by frequency spectrum, but also by the initial phase of each frequency component. To ensure a regime for the optimal effect, the rates of increase and drop in the modulating signal amplitude should be synchronized with dynamic processes in the biological object being exposed.