Clinical and Applied Aspects of Magnetic Field Exposure: Possible Role for the Endogenous Opioid Systems

Abstract

An extensive series of experiments has demonstrated that time-varying magnetic fields can influence the physiological and behavioral effects of exogenous opiates as well as the endogenous opioid systems in mice. Acute exposure to a variety of magnetic field conditions has been found to inhibit the analgesic and locomotor effects of morphine in CF-1 and C57BL mice, respectively. Exposure to magnetic fields also attenuates or eliminates the daily rhythm in morphine-induced analgesia. When endogenous opioid systems were activated by exposing mice to stressors, magnetic field exposure also inhibited the effects of the endogenous opioids. These biomagnetic effects may be mediated by alteration of pineal function after magnetic field exposure, or by changes in central calcium levels in brain tissue. These findings are discussed in relation to effects on growth processes, including tumorigenic processes, and on convulsive seizures. Effects of exposure to the magnetic fields associated with magnetic resonance imaging and those associated with electric powerlines are also addressed.