Study type: Medical/biological study (experimental study)

Effects of acute electromagnetic field exposure and movement restraint on antioxidant system in liver, heart, kidney and plasma of Wistar rats: A preliminary report. med./bio.

Published in: Int J Radiat Biol 2010; 86 (12): 1088-1094

Aim of study (acc. to author)

To evaluate the early effects of acute exposure (2 h) to extremely low frequency electromagnetic fields, as well as movement restraint (to induce psychological and physical stress) and the combination of both on the antioxidant systems in the plasma, liver, kidney, and heart of rats.

Background/further details

Cells can be protected against stress by exposing them first to a brief dose of the same or different stress (e.g. heat, chemicals, brief ischemia or electromagnetic field exposures). The authors tested the hypothesis that a brief exposure to extremely low frequency electromagnetic fields could induce adaptive changes on the antioxidant systems, particularly in those tissues with high oxidative metabolism like the liver, kidney and heart. This pre-conditioning could lead to protective effects against oxidative stress.
24 male rats were divided in two groups: restrained and unrestrained. The restrained animals were confined into an acrylic tube for 120 min. Half of the animals of each group (n=6) were exposed to extremely low frequency electromagnetic fields during the period of immobilization.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 60 Hz
Exposure duration: continuous for 2 hr

General information

animals were divided into four groups: i) in movement restrained ii) in movement restrained + exposure to EMF iii) in movement unrestrained + exposure to EMF iv) control - no restrainment + no exposure

Exposure 1

Main characteristics
Frequency 60 Hz
Type
Waveform
Exposure duration continuous for 2 hr
Exposure setup
Exposure source
Setup rats were restrained by confinement into a 18 cm long acrylic cylinder with an inner diameter of 7 cm; unrestained rats were placed in 47 cm x 25 cm x 21 cm acrylic cages; pair of circular Helmholtz coils with an inner diameter of 30 cm, consisting of 350 turns of 18-gauge copper wire, separated by 15 cm; coils lying on the upper and lower cage surfaces
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 2.4 mT - measured - -

Reference articles

  • Torres-Duran PV et al. (2007): Effects of whole body exposure to extremely low frequency electromagnetic fields (ELF-EMF) on serum and liver lipid levels, in the rat.

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

Glutathione concentration was significantly lower in the heart of all experimental animals when compared to the control group (i.e. no exposure, unrestraint); furthermore, the decrease was higher in the liver of both restrained groups (i.e. strongest decrease). Superoxide dismutase enzyme activity was lower in the plasma of all restrained and electromagnetic field exposed animals compared to the unrestrained and non-exposed control rats. There were no significant differences in catalase enzyme activity and thiobarbituric acid reactive substances levels among all the experimental groups vs. the control group.
The authors conclude that two hours of 60 Hz exposure might immediately alter the metabolism of free radicals, decreasing superoxide dismutase activity in plasma and glutathione content in heart and kidney, but does not induce immediate lipid peroxidation. Oxidative stress induced by movement restraint was stronger than that produced by electromagnetic field exposure.

Study character:

Study funded by

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