Neonatal exposure to 17α-ethinyl estradiol affects kisspeptin expression and LH-surge level in female rats.
Contamination of estrogenic compounds disrupts endocrinological and neurological reproductive systems in animals. Neonatal exposure to 17α-ethinyl estradiol (EE) induced an abnormal estrous cycle at postnatal day (PND) 180, but not at PND90. We found that serum level of luteinizing hormone (LH) at the latter half of proestrus in EE-treated rats was lower than in the controls at PND90 when there was no significant difference on estrous cyclicity. Additionally, kiss1 mRNA levels in the anteroventral periventricular nucleus-preoptic area (AVPV/POA) were lower in EE-treated rats than in the controls. The expression of GnRH precursor (GNRH1) mRNA in the AVPV/POA and that of LH beta subunit (LHb) mRNA in the pituitary were similar in the control- and EE-treated groups. Our results indicated that neonatal exposure to EE leads to reduced expression of kiss1 mRNA in AVPV/POA and LH-surge, which is likely related to the delayed reproductive dysfunction seen in adult female rats.
Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.
Kento
K
Usuda
Kentaro
K
Nagaoka
Kaori
K
Nozawa
Haolin
H
Zhang
Kazuyoshi
K
Taya
Midori
M
Yoshida
Gen
G
Watanabe
D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D004997:Ethinyl Estradiol / Q000009:adverse effects*; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects*; D059648:Kisspeptins / Q000378:metabolism*; D007986:Luteinizing Hormone / Q000097:blood*; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D012098:Reproduction / Q000187:drug effects*
C491406:Kiss1 protein, rat; D059648:Kisspeptins; D004997:Ethinyl Estradiol; D007986:Luteinizing Hormone