Developmental exposure to environmental estrogens alters anxiety and spatial memory in female mice.
Humans and wildlife are exposed to numerous anthropogenic drugs and pollutants. Many of these compounds are hormonally active, and recent evidence suggests that the presence of these endocrine disruptors permanently alters normal development and physiology in a variety of vertebrate species. Here, we report on the effects of developmental exposure to two common estrogenic pollutants, bisphenol A and ethinyl estradiol on sexually dimorphic, non-reproductive behavior. Mice (Mus musculus domesticus) were exposed to environmentally relevant levels of these chemicals (2 and 200 microg/kg/day for bisphenol A and 5 microg/kg/day for ethinyl estradiol) throughout prenatal and early postnatal development. As adults, the animals were observed in a variety of tests measuring sexually dimorphic behaviors including short-term spatial memory (in a radial-arm maze and a Barnes maze) and anxiety (in an elevated-plus maze and a light/dark preference chamber). Developmental exposure to ethinyl estradiol was found to masculinize behavior in all of the assays used. Bisphenol A increased anxious behavior in a dose-dependent fashion but had no effect on spatial memory. These results indicate that non-reproductive, sexually dimorphic behavior is sensitive to endocrine disruption. In addition, these experiments suggest that both humans and wildlife are being exposed to levels of these endocrine disrupting compounds that are sufficient to disrupt the development of the nervous system and that may have permanent consequences on sexually dimorphic behaviors.
Ryan
Bryce C
BC
Department of Zoology, North Carolina State University, Raleigh, NC 27695, USA. ryan.bryce@epa.gov
Vandenbergh
John G
JG
D000704:Analysis of Variance; D000818:Animals; D001007:Anxiety / Q000139:chemically induced; D001559:Benzhydryl Compounds; D004305:Dose-Response Relationship, Drug; D052244:Endocrine Disruptors / Q000494:pharmacology*; D004785:Environmental Pollutants / Q000494:pharmacology; D004997:Ethinyl Estradiol / Q000494:pharmacology*; D005106:Exploratory Behavior / Q000187:drug effects; D005260:Female; D018782:Maze Learning / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D010636:Phenols / Q000494:pharmacology*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000503:physiopathology*; D012727:Sex Characteristics; D012741:Sexual Maturation / Q000187:drug effects*; D013028:Space Perception / Q000187:drug effects; D013037:Spatial Behavior / Q000187:drug effects; D000098826:Bisphenol A Compounds
D001559:Benzhydryl Compounds; D052244:Endocrine Disruptors; D004785:Environmental Pollutants; D004997:Ethinyl Estradiol; D010636:Phenols; C006780:bisphenol A; D000098826:Bisphenol A Compounds