Study type: Medical/biological study (experimental study)

Acute exposure to low-level CW and GSM-modulated 900 MHz radiofrequency does not affect Ba(2+) currents through voltage-gated calcium channels in rat cortical neurons. med./bio.

Published in: Bioelectromagnetics 2007; 28 (8): 599-607

Aim of study (acc. to author)

To study the possibility that acute exposure to GSM modulated 900 MHz radiofrequency electromagnetic fields could modify the permeability of voltage-gated calcium channels in neurons.

Background/further details

Primary cultures of rat cortical neurons were used. Temperature in the Petri dishes were measured before, during, and after the exposure.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 900 MHz
Modulation type: CW
Exposure duration: repeated exposure: 1, 2, or 3 times 90 s at intervals of 2-3 min
Exposure 2: 900 MHz
Modulation type: pulsed
Exposure duration: repeated exposure: 1, 2, or 3 times 90 s at intervals of 2-3 min
  • SAR: 2 W/kg average over time

Exposure 1

Main characteristics
Frequency 900 MHz
Type
Exposure duration repeated exposure: 1, 2, or 3 times 90 s at intervals of 2-3 min
Modulation
Modulation type CW
Exposure setup
Exposure source
Chamber The exposure system, especially designed for electrophysiological patch-clamp recording, has been described in [Liberti et al., 2004]. An open propagating structure consisting of a Co-Planar Waveguide (22.0 cm x 10.2 cm x 0.4 cm) was positioned on the stage of a microscope. The upper side of the dielectric substrate (glass) was plated with three thin conductive gold layers leaving two windows for the visualization of the cell culture.
Setup A 35-mm Petri dish was held in the center of the exposure system by a 3-mm polystyrene mask.
Additional info The structure propagated only the fundamental mode (quasi-transverse electromagnetic mode) in which the direction of the EF was almost parallel to the Petri dish surface and orthogonal to the glass microelectrode, thus minimising interference. The system assured a good homogeneity of the field applied to the sample.
Parameters
Measurand Value Type Method Mass Remarks
SAR 2 W/kg - - - -

Exposure 2

Main characteristics
Frequency 900 MHz
Type
Exposure duration repeated exposure: 1, 2, or 3 times 90 s at intervals of 2-3 min
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

GSM-modulated

Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
SAR 2 W/kg average over time - - -

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The data indicate that single or multiple acute exposures to either continuous wave or GSM-modulated 900 MHz radiofrequency electromagnetic fields did not significantly alter the current amplitude or the current-voltage relationship of Ba2+ currents through voltage-gated calcium channels.

Study character:

Study funded by

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