Medical/biological study (experimental study)

Synaptic neurone activity under applied 50 Hz alternating magnetic fields med./bio.

By: Calvo AC, Azanza MJ

Published in: Comp Biochem Physiol C Pharmacol Toxicol Endocrinol 1999; 124 (1): 99-107

Journal partially peer-reviewed/peer-review process unclear

Aim of study (acc. to author)

To study the effect of 50 Hz magnetic field of 1-15 mT intensity on the synaptic neuron activity mediated by acetylcholine and glutamate.

Background/further details

The experiments were performed on 40 single neuron units from the sub-oesophageal ganglia of the snail (Helix aspersa). To study neuron activity a series of experiments was performed by applying glutamate and acetylcholine as putative neurotransmitters. Caffeine was also applied. Different Ringer solutions have been applied (K⁺ free; five times the normal K⁺ concentration; Ca²⁺ free; five times the normal Ca²⁺ concentration).

Endpoint

cell function: neuron synaptic activity (firing rate, spike frequency, bursting)

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: 15 s	magnetic flux density: 1 mT peak value (1 - 15 mT)

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Exposure duration	15 s

Exposure setup

Exposure source	Helmholtz coils
Chamber	Faraday cage
Setup	pair of Helmholtz coils; samples placed between the coils

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	1 mT	peak value	measured	-	1 - 15 mT

Exposed system:

intact cell/cell culture
snail neurons (Helix aspersa)

Methods Endpoint/measurement parameters/methodology

cell function: neurone synaptic activity (firing rate, spike frequency, bursting)

Investigated system:

intact cell/cell culture

Time of investigation:

before exposure
during exposure
after exposure

Main outcome of study (acc. to author)

The applied 50 Hz alternating magnetic field did not modify the synaptic neuron activity induced by glutamate or acetylcholine on neurones. The applied 50 Hz magnetic fields mimiced the synaptic effect of glutamate. A mimic effect was also observed for the neuronal effects of 50 Hz magnetic fields and caffeine. The application of Ringer solutions suggested that Ca²⁺ ions were involved in the elicited responses to either caffeine, glutamate or 50 Hz magnetic fields.
The authors concluded that the mimic induced effects for 50 Hz magnetic fields, caffeine and glutamate on neurones corrobate that Ca²⁺ ions are the cytosolic effectors of the applied 50 Hz magnetic field interaction with neuron plasma membrane.

Study character:

medical/biological study
experimental study
full/main study

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