Medical/biological study (experimental study)

Extremely low-frequency magnetic fields effects on the snail single neurons med./bio.

By: Partsvania B, Sulaberidze T, Modebadze Z, Shoshiashvili L

Published in: Electromagn Biol Med 2008; 27 (4): 409-417

Aim of study (acc. to author)

To study the influence of extremely low frequency electromagnetic fields utilized in cell phones on the habituation process of the mollusk single neuron to intracellular stimuli.

Background/further details

Habituation is regarded as a form of non learning, in which responses to repeated stimuli decrease over time. Individual neurons react to stimulant intracellular impulses with action potentials and then habituation arises. 33 different nerve preparations (giant neurons) were used for each stimulation condition: Neuron 3 of the left parietal ganglion and neuron 3 of the right parietal ganglion.
At the beginning of the recording the threshold of action potential triggering was determined. The amplitude was increased until action potential appeared as a reaction. Intracellular stimulation was continued after establishing habituation and at the same time the neuron was exposed to magnetic fields.

Endpoint

cell function: neuron habituation

Exposure

- magnetic field
- low frequency

Exposure	Parameters
Exposure 1: 8.34–217 Hz Exposure duration: not given	magnetic flux density: 1 mT peak value magnetic flux density: 6 mT peak value (1 - 6 mT)

Exposure 1

Main characteristics

Frequency	8.34–217 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	not given

Exposure setup

Exposure source	Helmholtz coils
Setup	pair of Helmholtz coils with a diameter of 11 cm, 5.5 cm apart; cells placed in the center of the coil system

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	1 mT	peak value	calibration	-	-
magnetic flux density	6 mT	peak value	calibration	-	1 - 6 mT

Exposed system:

brain ganglion of the mollusk Helix pomatia

Methods Endpoint/measurement parameters/methodology

cell function: neuron habituation: action potential (standard microelectrode technique)

Investigated system:

brain ganglion of the mollusk Helix pomatia

Time of investigation:

before exposure
during exposure

Main outcome of study (acc. to author)

Exposure of the neuron to the low frequency electromagnetic fields caused dehabituation to the intracellular stimulus, i.e. the neuron restarted to to trigger action potentials. The dehabituation depends on the frequency of the extremely low frequency magnetic field. The effect was proportional to the magnetic induction peak value.
The results indicate that athermal magnetic field exposures can alter habituation in brain neurons. The observed dehabituation by electromagnetic fields might be regarded as destruction of the normal functioning of the neuron.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

International Science and Technology Center (ISTC), Russia

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