ABSTRACT

Purpose:

To determine whether concentrations in the brain and plasma tissues are infl uenced by ELF magnetic fields

Methods:

Male, 250-300 g guinea pigs were kept under the laboratory conditions of 23 °C, a day and night cycle of 12 hours and an ambient geomagnetic fi eld of 30 μT (microTeslas) in plastic cages. The subjects were divided into two groups: a control group (n=11) and an experimental group (n=24), which was exposed to a 50 Hz, 2 mT fi eld for 4 hours/day for 5 days. The control subjects were handled in an identical manner without being exposed to any magnetic fi eld. After the completion of the experiment, blood samples from the control and exposed animals were collected by cardiac puncture without hemolysis. The animals were sacrificed by ether inhalation in a closed box; then their brains were dissected out immediately. Cu++, Zn++, Ca++ and Mg++ concentrations in both the plasma and brain tissue of guinea pigs were determined by fl ame atomic absorption. Na+ and K+ concentrations in the plasma were measured by direct application to fl ame photometry.

Results:

Na+, Ca++ and Mg++ concentrations in the blood plasma increased while Zn++ and K+ concentrations decreased with the effect of the magnetic fi eld. The increase in the Ca++ concentration was statistically significant. The Cu++ concentration was not affected by magnetic field exposure. The magnetic field, having a greater effect on Zn++ and Mg++ concentrations, increased Cu++, Zn++, Ca++ and Mg++ concentrations in the brain tissue.

Conclusion:

The ELF magnetic fi eld altered the Ca++ concentration in the brain and plasma tissues. It is generally thought that the cell membrane is the first target of external fi elds, and calcium regulated activity is involved in ELF fi eld coupling to living systems. Our results appear consistent with this hypothesis