Amplitude windows and transiently augmented transcription from exposure to electromagnetic fields.

The exposure of cells to relatively low-intensity, pulsed, low-frequency electromagnetic fields can result in a transient augmentation of mRNA synthesis. Under certain conditions of irradiation, the augmentation is a function of the strength of the electromagnetic field. A linear, multi-step, chemical-reaction model accounts for many of the principal features that are observed in both the time- and intensity-dependent variations of transcriptional effects. The crucial assumption in the model is that the direct effect of electromagnetic fields on exposed cells is an increase in the rate constant that characterizes one of the intermediate sequential reactions in the synthesis of mRNA.