Study type: Medical/biological study (experimental study)

Influence of extremely low frequency magnetic fields on Ca2+ signaling and NMDA receptor functions in rat hippocampus. med./bio.

Published in: Neurosci Lett 2007; 413 (2): 145-149

Aim of study (acc. to editor)

This study was performed to analyze the effects of an extremely low frequency magnetic field on Ca2+-dependent enzyme activities and its possible relation to NMDA receptor function in rat hippocampus.

Background/further details

Hippocampi were obtained from brains of 3 weeks old rats. Three exposure groups were performed with six animals each.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: 90 days

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration 90 days
Exposure setup
Exposure source
Chamber animal movements were measured with a photoelectric sensor connected to the base of the cage and a digital counter
Setup two sets of Helmholtz coils with 25 turns each
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 50 µT average over time measured - -
magnetic flux density 100 µT average over time measured - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

Exposed rats exhibited increased physical activity, especially during night periods, compared to the control group.
The exposure to the extremely low frequency magnetic field caused increased intracellular Ca2+ level concomitant with increased Ca2+-dependent enzyme activities (protein kinase C, cAMP-dependent protein kinase and calcineurin (a protein phosphatase)) as well as a decreased activity of Ca2+-calmodulin-dependent protein kinase in the hippocampus. Additionally, decreased glutamate binding to NMDA receptors were revealed, indicating lower activation of this receptor.
The results of this study were more pronounced in magnetic flux density of 100 µT compared to 50 µT.

Study character:

Study funded by

Related articles