Medical/biological study (experimental study)

Urinary 6-sulphatoxymelatonin excretion is increased in rats after 24 hours of exposure to vertical 50 Hz, 100 microT magnetic field med./bio.

By: Bakos J, Nagy N, Thuroczy G, Szabo LD

Published in: Bioelectromagnetics 1997; 18 (2): 190-192

Aim of study (acc. to author)

To investigate the effect of a 50 Hz magnetic field (MF) exposure on 6-sulphatoxymelatonin urinary excretion in rats. This study was a self-controlled experiment of a previous study (q.v. publication 1241). However, a magnetic flux density of 100 µT was applied in this study .

Background/further details

6-sulphatoxymelatonin is the major metabolite of melatonin and can be determined easily non-invasively in excreted urine.
A total of 10 adult, male rats was used (divided into 2 groups: MF-exposed (100 µT) and sham exposed (1 µT, stray field)). A light (9 h)/dark (15 h) cycle was maintained. (light on at 4 AM / light off at 7 PM). Urine was collected twice a day (i.e. at the end of the dark phase and light phase, respectively) over a period 5 consecutive days. The magnetic field was turned on at 7 AM on day 3 and turned off at 7 AM on day 4 (total MF exposure time 24 h).

Endpoint

endocrine changes: melatonin metabolism

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: 24 h	magnetic flux density: 100 µT unspecified (unspecified) (vertical MF)

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	24 h

Exposure setup

Exposure source	two double wound coil, inner diameter 42 cm, connected to an AC generator
Chamber	metabolic cages

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	100 µT	unspecified	-	unspecified	vertical MF

Reference articles

Bakos J et al. (1995): Sinusoidal 50 Hz, 500 microT magnetic field has no acute effect on urinary 6-sulphatoxymelatonin in Wistar rats

Exposed system:

animal
rat/Wistar
whole body

Methods Endpoint/measurement parameters/methodology

endocrine changes: amount of 6-sulphatoxymelatonin in excreted urine (radioimmunoassay)

Investigated system:

isolated bio./chem. substance
6-sulphatoxymelatonin

Investigated organ system:

endocrine system

Time of investigation:

before exposure
during exposure
after exposure

Main outcome of study (acc. to author)

One night after completion of MF exposure, rate of 6-sulphatoxymelatonin increased significantly compared with the rate on the day of exposure, but not significantly compared with the rates of the days before exposure.

Study character:

medical/biological study
experimental study
full/main study
replication/reproduction study
brief communication

Study funded by

not stated/no funding

Replicated studies

Bakos J et al. (1995): Sinusoidal 50 Hz, 500 microT magnetic field has no acute effect on urinary 6-sulphatoxymelatonin in Wistar rats

Seifpanahi-Shabani H et al. (2016): Long-term Exposure to Extremely Low Frequency Electromagnetic Field and Melatonin Production by Blood Cells
Dyche J et al. (2012): Effects of power frequency electromagnetic fields on melatonin and sleep in the rat
Davis S et al. (2006): Effects of 60-Hz magnetic field exposure on nocturnal 6-sulfatoxymelatonin, estrogens, luteinizing hormone, and follicle-stimulating hormone in healthy reproductive-age women: results of a crossover trial
Gobba F et al. (2006): No association between occupational exposure to ELF magnetic field and urinary 6-sulfatoximelatonin in workers
Bakos J et al. (2002): One week of exposure to 50 Hz, vertical magnetic field does not reduce urinary 6-sulphatoxymelatonin excretion of male wistar rats
Chacon L (2000): 50-Hz Sinusoidal Magnetic Field Effect On In Vitro Pineal N-Acetyltransferase Activity
Heikkinen P et al. (1999): Chronic exposure to 50-Hz magnetic fields or 900-MHz electromagnetic fields does not alter nocturnal 6-hydroxymelatonin sulfate secretion in CBA/S mice
Selmaoui B et al. (1999): Age-related differences in serum melatonin and pineal NAT activity and in the response of rat pineal to a 50-Hz magnetic field
Bakos J et al. (1999): Urinary 6-Sulphatoxymelatonin Excretion of Rats is not Changed by 24 Hours of Exposure to A Horizontal 50-Hz, 100-μT Magnetic Field
Bakos J et al. (1995): Sinusoidal 50 Hz, 500 microT magnetic field has no acute effect on urinary 6-sulphatoxymelatonin in Wistar rats