Study type: Medical/biological study (experimental study)

Transient effect of weak electromagnetic fields on calcium ion concentration in Arabidopsis thaliana. med./bio.

Published in: BMC Plant Biol 2009; 9 (1): 47

Aim of study (acc. to editor)

To study the effect of weak electromagnetic fields on calcium ion concentration in the plant Arabidopsis thaliana.

Background/further details

An aequorin expressing Arabidopsis thaliana mutant was subjected to a magnetic field around 65 µT and an electromagnetic field with the corresponding Ca2+ cyclotron frequency of 50 Hz. The applied ion cyclotron resonance (ICR) is one of the discussed mechanisms, predicting biological effects for definite frequencies and intensities of electromagnetic fields possibly by affecting the physiological availability of small ions.
The aequorin producing Arabidopsis mutant facilitates a powerful way to study the cytosolic Ca2+ flux in response to exogenic stressors.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: DC continuous through the whole experiment; AC up to 90 min superimposed
Exposure 2: 50 Hz
Exposure duration: DC continuous through the whole experiment; AC up to 90 min superimposed
Exposure 3: 50 Hz
Exposure duration: DC continuous through the whole experiment; AC up to 90 min superimposed

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Exposure duration DC continuous through the whole experiment; AC up to 90 min superimposed
Additional info superimposed on a DC field
Exposure setup
Exposure source
Setup two pairs of Helmholtz coils with an inner diameter of 13 cm, wired one on the other, placed inside a permalloy shielding box; 200 turns for DC and 100 turns for AC field generation; sample dish placed in the centerr of the vertical axcis of the coil pairs
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 65.8 µT average over time measured - DC field
magnetic flux density 5 µT average over time measured - AC field

Exposure 2

Main characteristics
Frequency 50 Hz
Type
Exposure duration DC continuous through the whole experiment; AC up to 90 min superimposed
Additional info superimposed on a DC field
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 65 µT average over time measured - DC field
magnetic flux density 0.1 µT average over time measured - 0.1 µT, 1.5µT, 20 µT AC field

Exposure 3

Main characteristics
Frequency 50 Hz
Type
Exposure duration DC continuous through the whole experiment; AC up to 90 min superimposed
Additional info superimposed on a DC field
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 2 µT average over time measured - 2 µT, 55µT, 65 µT, 75 µT DC field
magnetic flux density 5 µT average over time measured - AC field

Reference articles

  • Pazur A et al. (2006): Growth of etiolated barley plants in weak static and 50 Hz electromagnetic fields tuned to calcium ion cyclotron resonance.
  • Carson JJL et al. (1996): Fluorescence spectrophotometer for the real time detection of cytosolic free calcium from cell suspensions during exposure to extremely low frequency magnetic fields.

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • before exposure
  • during exposure

Main outcome of study (acc. to author)

The data suggest for the first time a direct and rapid influence of the resonant electromagnetic excitation of the cyclotronic frequency of Ca2+ on the concentration of this ion in the cytosol. This change was transient and relaxed within 60 minutes. Ca2+ transients were observed both by switching the Ca2+ ICR condition on and off.
Considering the various functions of Ca2+ as a second messenger in plants, this mechanism may be relevant for perception of these combined fields.

Study character:

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