Medical/biological study (experimental study)

The effects of prenatal and postnatal exposure to electromagnetic field on rat ovarian tissue. med./bio.

By: Burcu A, Nevin E, Ilkay A, Amac K, Alper BH, Muge K

Published in: Toxicol Ind Health 2020; 36 (12): 1010-1018

Aim of study (acc. to author)

The effects of prenatal and postnatal exposure of rats to a 50 Hz magnetic field on the ovarian structure and function should be investigated.

Background/further details

Pregnant rats were either exposed to the magnetic field or sham exposed (n=4 each) from the first day of pregnancy. A total of 12 pups from exposed mothers (exposure group) and 10 pups from sham exposed mothers (sham exposure group) were further exposed and sham exposed, respectively, after birth for 42 days. All pups were sacrificed and investigated then.

Endpoint

effects on the reproductive system: ovarian structure and function

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: from first day of pregnancy until postnatal day 42 for 4 h/day on 5 days/week	magnetic flux density: 3 mT

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Exposure duration	from first day of pregnancy until postnatal day 42 for 4 h/day on 5 days/week

Exposure setup

Exposure source	Helmholtz coils
Chamber	plastic cages
Setup	Helmholtz coil pair (95 cm in diameter); each coil was made of 320 turns of 2.5-mm copper wire mounted on a wooden frame; the distance between the coils was 33 cm; rats were kept in plastic cages placed between coils during exposure
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	3 mT	-	measured	-	-

Measurement and calculation details

the teslameter accuracy was ± 2%

Reference articles

Tayefi H et al. (2010): The effects of prenatal and neonatal exposure to electromagnetic fields on infant rat myocardium.

Exposed system:

animal
rat/Sprague Dawley (adults, fetuses and neonates)
whole body

Methods Endpoint/measurement parameters/methodology

effects on the reproductive system: histology (hematoxylin-eosin stain and Masson trichrome stain, light microscopy), total protein level (BCA protein assay), levels of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) in ovarian tissue (ELISA, immunohistochemistry), serum levels of follicle stimulating hormone, luteinizing hormone and estradiol (spectrophotometry)
body weight

Investigated system:

isolated bio./chem. substance
tissue slices
isolated organ
blood, ovaries

Investigated organ system:

reproductive system

Time of investigation:

after exposure

Main outcome of study (acc. to author)

Follicle stimulating hormone and iNOS levels were significantly higher and the estradiol level was significantly lower in the exposure group compared to the sham exposure group. Moreover, in the exposure group, fibrosis, congestion, bleeding areas, and degeneration of follicle structures were observed in ovarian tissue.
The authors conclude that prenatal and postnatal exposure of rats to a 50 Hz magnetic field might impair the ovarian structure and function.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Dokuz Eylul University, Turkey

Franczak A et al. (2020): Consequences of electromagnetic field (EMF) radiation during early pregnancy - androgen synthesis and release from the myometrium of pigs in vitro.
Khaki AA et al. (2016): The effect of Non-ionizing electromagnetic field with a frequency of 50 Hz in Rat ovary: A transmission electron microscopy study.
Bakacak M et al. (2015): The effects of electromagnetic fields on the number of ovarian primordial follicles: An experimental study.
Roshangar L et al. (2014): Effect of low-frequency electromagnetic field exposure on oocyte differentiation and follicular development.
de Bruyn L et al. (2010): Effect of long-term exposure to a randomly varied 50 Hz power frequency magnetic field on the fertility of the mouse.
Tayefi H et al. (2010): The effects of prenatal and neonatal exposure to electromagnetic fields on infant rat myocardium.
Rajaei F et al. (2010): Effects of extremely low-frequency electromagnetic field on fertility and heights of epithelial cells in pre-implantation stage endometrium and fallopian tube in mice.
Aydin M et al. (2009): Evaluation of hormonal change, biochemical parameters, and histopathological status of uterus in rats exposed to 50-Hz electromagnetic field.
Al-Akhras MA (2008): Influence of 50 Hz magnetic field on sex hormones and body, uterine, and ovarian weights of adult female rats.
Roushangar L et al. (2007): Ultrastructural alterations and occurrence of apoptosis in developing follicles exposed to low frequency electromagnetic field in rat ovary.
Al-Akhras MA et al. (2006): Influence of 50 Hz magnetic field on sex hormones and other fertility parameters of adult male rats.
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.
Mostafa RM et al. (2006): Sex hormone status in male rats after exposure to 50 Hz, 5 mTesla magnetic field.
Aksen F et al. (2006): Effect of 50-Hz 1-mT magnetic field on the uterus and ovaries of rats (electron microscopy evaluation).
Al-Akhras MA et al. (2001): Effects of extremely low frequency magnetic field on fertility of adult male and female rats.