The Sensitivity of Cells and Tissues to Exogenous Fields: Dependence Upon Target System Initial State

Abstract

Reports of biological windows in the responses of cells and tissues to exogenous environmental and therapeutic electromagnetic fields (EMF), suggest the electrical impedance of the target plays an important role in EMF sensitivity1,2. Biological windows have been reported at the cellular and animal level3-9. In addition, specialized waveforms such as inductively coupled pulsed EMF (PEMF) signals for recalcitrant fracture repair10 and pulsed radio frequency (PRF) signals for soft tissue repair, edema reduction and wound healing11 suggest windowing. The clinical significance of windowing phenomena is evidenced by the fact that only repairing bone, and not the surrounding normal bone has a physiologically relevant response to PEMF and that waveform parameters play a critical role in the clinical effectiveness of therapeutic EMF signals12. Although exact transduction pathways are unclear, these studies indicate that cells and tissues exhibit biological, as well as biophysical, windows in their response to a variety of exogenous EMF signals.