Electromagnetic Controls Over Biological Growth Processes

Bioelectromagnetics in morphogenesis

Understanding the factors that allow biological systems to reliably self-assemble consistent, highly complex, four dimensional patterns on many scales is crucial for the biomedicine of cancer, regeneration, and birth defects. The role of chemical signaling factors in controlling embryonic morphogenesis has been a central focus in modern developmental biology. While the role of tensile forces is also beginning to be appreciated, another major aspect of physics remains largely neglected by molecular embryology: electromagnetic fields and radiations. The continued progress of molecular approaches to understanding biological form and function in the post genome era now requires the merging of genetics with functional understanding of biophysics and physiology in vivo. The literature contains much data hinting at an important role for bioelectromagnetic phenomena as a mediator of morphogenetic information in many contexts relevant to embryonic development. This review attempts to highlight briefly some of the most promising (and often underappreciated) findings that are of high relevance for understanding the biophysical factors mediating morphogenetic signals in biological systems. These data originate from contexts including embryonic development, neoplasm, and regeneration.

Increased mortality in land snails (Cepaea nemoralis) exposed to powerline (60-Hz) magnetic fields and effects of the light-dark cycle

The effects of various durations (0.5, 2, 12, 48, or 120 h) of day- and night-time exposures to a 1.0 gauss (rms) 60-Hz magnetic field or sham field on mortality levels in the nocturnally-crepuscularly active land snail, Cepaea nemoralis, were examined. These snails were injected with morphine or saline vehicle and tested for reaction to an aversive thermal stimulus as part of another study. Mortality levels were monitored over a 2-week period following the initial exposure to the fields and were shown not to be differentially affected by the drug injection procedures. Mortality levels increased linearly as a function of increased length of exposure to the magnetic fields (P less than 0.001) but not when exposed to the sham fields. As well, night-time exposures resulted in greater mortality levels than day-time exposures (P less than 0.025). These results indicate that day-night rhythms are important in determining the magnitude of the magnetic field exposure effect. It is speculated that the magnetic fields may disrupt endogenous opioid- and calcium-modulated homeostatic mechanisms and augment stress effects, modifying a variety of systems including immunocompetence.

Magnetic fields and stress: day-night differences

An exposure for 30 min to a 0.5 Hz rotating magnetic field (1.5-90 G) significantly reduced warm water swim stress-induced opioid analgesia in CF-1 male mice. Pre-treatment with naloxone (1.0 mg/kg) had comparable inhibitory effects on warm water swim induced analgesia. The magnetic stimuli also eliminated the day-night rhythm in stress-induced analgesia, with maximum inhibitory effects occurring in the dark period when peak analgesia was present. These results indicate that magnetic stimuli can significantly alter day-night rhythms of stress-induced activation of endogenous opioid systems and their behavioral and physiological consequences. These elevated night time effects may involve actions on the pineal gland, while the day time actions may involve alterations in the distribution and transport of Ca++ and or other divalent ions.