Medical/biological study (experimental study)

Increase in hypoxanthine-guanine phosphoribosyl transferase gene mutations by exposure to electric field med./bio.

By: Ding GR, Wake K, Taki M, Miyakoshi J

Published in: Life Sci 2001; 68 (9): 1041-1046

Aim of study (acc. to author)

This study was performed to investigate whether the results of a previous study (see publication 2074) concerning increased hypoxanthine-guanine phosphoribosyl transferase gene mutations were induced by the exposure to magnetic field, electric field or both.

Endpoint

genotoxicity/mutation: hypoxanthine-guanine phosphoribosyl transferase gene mutation

Exposure

- 50/60 Hz
- electric field

Exposure	Parameters
Exposure 1: 60 Hz Exposure duration: 10 h (exposed or sham exposed)	electric field strength: 10 V/m maximum

Exposure 1

Main characteristics

Frequency	60 Hz
Type	electric field
Waveform	sinusoidal
Exposure duration	10 h (exposed or sham exposed)

Exposure setup

Exposure source	three platium electrodes
Chamber	15 cm diameter dish
Setup	electrodes with plastic holders installed in a dish in CO2 incubator
Additional info	for sham exposure, the potential remains at 0 mV.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
electric field strength	10 V/m	maximum	measured	-	-

Additional parameter details

The voltage of one electrode mentained at 450 mV and the others grounded at 0 mV. The potential increases as the distance of middle electrode increases .

Reference articles

Miyakoshi J et al. (1996): Increase in hypoxanthine-guanine phosphoribosyl transferase gene mutations by exposure to high-density 50-Hz magnetic fields

Exposed system:

intact cell/cell culture
CHO (Chinese hamster ovary) cells

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: hypoxanthine-guanine phosphoribosyl transferase gene mutation (number of 6-thioguanine resistent colonies)

Investigated system:

intact cell/cell culture

Time of investigation:

after exposure

Main outcome of study (acc. to author)

The hypoxanthine-guanine phosphoribosyl transferase mutant frequency by electric field exposure was an approximate 2-fold of that by sham-exposure.
These data suggest that the observed increase in hypoxanthine-guanine phosphoribosyl transferase gene mutations of the previuos study were caused, in part, due to the induced electric field.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Association of Radio Industries and Businesses (ARIB), Japan
Research for Future Program, Japan Society for the Promotion of Science (JSPS), Japan

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