Artificial reproduction of magnetic fields produced by a natural geomagnetic storm increases systolic blood pressure in rats

Abstract

The incidence of geomagnetic storms may be associated with changes in circulatory physiology. The way in which the natural variations of the geomagnetic field due to solar activity affects the blood pressure are poorly understood and require further study in controlled experimental designs in animal models. In the present study, we tested whether the systolic arterial pressure (AP) in adult rats is affected by simulated magnetic fields resembling the natural changes of a geomagnetic storm. We exposed adult rats to a linear magnetic profile that simulates the average changes associated to some well-known geomagnetic storm phases: the sudden commencement and principal phase. Magnetic stimulus was provided by a coil inductor and regulated by a microcontroller. The experiments were conducted in the electromagnetically isolated environment of a semi-anechoic chamber. After exposure, AP was determined with a non-invasive method through the pulse on the rat's tail. Animals were used as their own control. Our results indicate that there was no statistically significant effect in AP when the artificial profile was applied, neither in the sudden commencement nor in the principal phases. However, during the experimental period, a natural geomagnetic storm occurred, and we did observe statistically significant AP increase during the sudden commencement phase. Furthermore, when this storm phase was artificially replicated with a non-linear profile, we noticed a 7 to 9 % increase of the rats' AP in relation to a reference value. We suggested that the changes in the geomagnetic field associated with a geomagnetic storm in its first day could produce a measurable and reproducible physiological response in AP.

Biological effects related to geomagnetic activity and possible mechanisms

“…The research concluded that variations in the geomagnetic field associated with the commencement and main phase of the geomagnetic storm led to an increase in arterial pressure of the rats with respect to the reference value derived from several control measurements when the geomagnetic field was quiet. The same results were reproduced in experiments with a simulation of the 2‐h interval of the geomagnetic storm that occurred on February 18–19, 2014, that were performed in the direction of geomagnetic H‐component [Martinez‐Breton and Mendoza, ; Martinez‐Breton et al, ].…”

Linkages Between Geomagnetic Activity and Blood Pressure

“…A well-controlled laboratory study in which nine young men were exposed to simulated GMFs that mimicked quiet or stormy days failed to demonstrate an impact on either SBP or DBP [71]. However, a reduction in nailfold capillary blood velocity was noted to occur, especially in the evening hours.…”