Inhibition of Melatonin in the Plasma of Third-Generation Male Mice under the Action of ELF Magnetic Fields

Abstract

2 3 4 ABSTRACTThe pineal gland has been considered a magnetic receptor organ that regulates circadian rhythms by means of the secretion of melatonin, a potent oncostatic agent that prevents the initiation and promotion of cancer. ELF electromagnetic radiation, similar to that generated by power lines, can alter melatonin plasma levels.To study this effect, 4 OF1 mice generations have been reared subjected to a lifelong 15 pT, 50 Hz magnetic field action. This magnetic field was generated inside a Helmholtz coil system. The concentration of melatonin in the blood has been determined on 40 male mice of the third generation by means of RIA, as they reached sexual maturity (3 months). Electromagn Biol Med Downloaded from informahealthcare.com by ThULB Jena on 11/17/14For personal use only. 76 PICAZO E T AL.A radical decrease, more remarkable at night, of the melatonin plasma levels and the loss of the night-day secretion rhythm was observed in the experimental group. These results could be the consequence of the applied magnetic field cumulative effect. The secretion rhythms of other hormones, at the level of the hypothalamic-hypophyseal axis, might be altered as an effect of those results. This chronobiological change could explain the different findings in the 4 generations of mice subjected to the same experimental model.

Blood melatonin and prolactin concentrations in dairy cows exposed to 60 Hz electric and magnetic fields during 8 h photoperiods

“…In rodents, the evidence for suppression of MLT by EMF exposure is inconsistent. Whereas, some studies show suppression [Grota et al, 1994;Kato et al, 1994;Mevissen et al, 1996;Picazo et al, 1998], others show no effects [John et al, 1998;Bakos et al, 2002]. In humans, several studies have demonstrated an EMF induced suppression of MLT [Wood et al, 1998;Graham et al, 2000;Griefahn et al, 2001].…”