Dundar Bumin, Cesur Gokhan, Comlekci Selcuk, Songur Ahmet, Gokcimen Alparslan, Sahin Onder, Ulukut Ozlem, Yilmaz H Ramazan, Sutcu Recep, Caliskan Sadettin
Department of Pediatric Endocrinology, Suleyman Demirel University, Cunur, Isparta, Turkey.
Toxicol Ind Health. 2009 Aug;25(7):479-87. doi: 10.1177/0748233709345942.
To investigate prenatal and post-natal effects of extremely low frequency (ELF) electric field (EF) on growth and pubertal development, pregnant Wistar rats were randomly distributed among three groups. The pregnant rats of the prenatal group were exposed to 24-hour EF at 50 Hz EF 10 kV/min during pregnancy and their subsequent randomly selected female pups continued to be exposed until puberty. The post-natal group was unexposed to EF during pregnancy, but randomly selected female pups from this group were exposed to EF between delivery and puberty at the same doses and duration as the prenatal group. The third group was a sham-exposed group. The mean birth weight and weight gain of the pups during study period were found significantly reduced in prenatal group than post-natal and sham-exposed groups (p < 0.001). No difference could be found among the three groups for body weight at puberty (p > 0.05). The mean age at vaginal opening and estrous were significantly higher at prenatal group than post-natal and sham-exposed groups (p < 0.001). Serum insulin-like growth hormone-1 (IGF-1) levels were found significantly reduced in prenatal exposure group compared with the other two groups (p < 0.001). There was no difference for birth weight, weight gain, the mean age at vaginal opening and estrous and IGF-1 levels between post-natal and sham-exposed groups (p > 0.05). There was also no difference for FSH, LH and E2 levels at puberty among the three groups (p > 0.05). Histological examination revealed that both the prenatal and post-natal groups had the evidence of tissue damage on hypothalamus, pituitary gland and ovaries. In conclusion, early beginning of prenatal exposure of rats to 24 hours 50 Hz EF at 10 kV/m until puberty without magnetic field (MF) resulted in growth restriction, delayed puberty and reduced IGF-1 levels in female Wistar rats. These effects probably associated with direct toxic effects of EF on target organs. Post-natal exposure to EF at similar doses and duration seems to be less harmful on target organs. Post-natal exposure to EF at similar doses and duration seems to be less harmful.
为研究极低频（ELF）电场（EF）对产前和产后生长及青春期发育的影响，将怀孕的Wistar大鼠随机分为三组。产前组的怀孕大鼠在孕期暴露于50赫兹、电场强度为10 kV/m的24小时ELF电场中，随后随机挑选的雌性幼崽持续暴露直至青春期。产后组在孕期未暴露于ELF电场，但从该组随机挑选的雌性幼崽在分娩至青春期期间以与产前组相同的剂量和时长暴露于ELF电场。第三组为假暴露组。研究发现，产前组幼崽的平均出生体重和研究期间的体重增加显著低于产后组和假暴露组（p < 0.001）。三组在青春期时的体重无差异（p > 0.05）。产前组阴道开口和发情的平均年龄显著高于产后组和假暴露组（p < 0.001）。与其他两组相比，产前暴露组的血清胰岛素样生长激素-1（IGF-1）水平显著降低（p < 0.001）。产后组和假暴露组在出生体重、体重增加、阴道开口和发情的平均年龄以及IGF-1水平方面无差异（p > 0.05）。三组在青春期时的促卵泡生成素（FSH）、促黄体生成素（LH）和雌二醇（E2）水平也无差异（p > 0.05）。组织学检查显示，产前组和产后组在下丘脑、垂体和卵巢均有组织损伤迹象。总之，大鼠在无磁场（MF）情况下，从产前开始直至青春期每天24小时暴露于50赫兹、10 kV/m的ELF电场，会导致雌性Wistar大鼠生长受限、青春期延迟和IGF-1水平降低。这些影响可能与ELF电场对靶器官的直接毒性作用有关。产后以相似剂量和时长暴露于ELF电场对靶器官的危害似乎较小。产后以相似剂量和时长暴露于ELF电场似乎危害较小。
