Study type: Medical/biological study (experimental study)

Exposure to extremely low frequency magnetic fields enhances locomotor activity via activation of dopamine D1-like receptors in mice. med./bio.

Published in: J Pharmacol Sci 2007; 105 (4): 367-371

Aim of study (acc. to author)

To study whether dopaminergic receptors were involved in extremely low frequency magnetic field induced behavioral changes, because in a previous study (publication 10671), the authors found that exposure to an extremely low frequency magnetic field increased levels of dopamine and its metabolites in the rat striatum.

Background/further details

30 minutes before exposure mice were treated with SCH23390 hydrochloride (SCH, D1-like antagonist) at 0.03 or 0.1 mg/kg or (RS)-(±) sulpiride (Sulp, D2-like antagonist) at 10 or 20 mg/kg.
It is known that dopaminergic D1-like receptor stimulation leads to a robust induction of striatal c-Fos expression.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 60 Hz
Exposure duration: 1 h/day for 1 or 7 days

Exposure 1

Main characteristics
Frequency 60 Hz
Type
Exposure duration 1 h/day for 1 or 7 days
Exposure setup
Exposure source
Setup three Helmholtz coils in a wooden frame parallel to each other
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 0.3 mT - - - -
magnetic flux density 2.4 mT - - - -

Reference articles

  • Lee BC et al. (2001): Prenatal exposure to magnetic field increases dopamine levels in the striatum of offspring.

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

Exposure to extremely low frequency magnetic field for one or seven days enhanced locomotor activity in a time-dependent manner. This hyperlocomotor activity paralleled an increase in c-Fos-like immunoreactivity. Pretreatment with a dopaminergic D1-like receptor antagonist (SCH23390), but not with a dopaminergic D2-like receptor antagonist (sulpiride), inhibited magnetic field-induced increased locomotor activity and c-Fos-immunoreactivity.
Thus, the data indicate that extremely low frequency magnetic field-induced behavioral responses are, at least in part, mediated by activation of dopamine D1-like receptors.

Study character:

Study funded by

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