title: Two-hit exposure to polychlorinated biphenyls at gestational and juvenile life stages: 1. Sexually dimorphic effects on social and anxiety-like behaviors.
abstract: Endocrine disrupting chemicals (EDCs) are widespread environmental contaminants that affect many neuroendocrine functions. The brain is particularly vulnerable to EDCs during critical periods of gestational development when gonadal hormones exert organizational effects on sexually dimorphic behaviors later in life. Peripubertal development is also a time of continued neural sensitivity to organizing effects of hormones, yet little is known about EDC actions at these times. We sought to determine effects of prenatal or juvenile exposures to a class of EDCs, polychlorinated biphenyls (PCBs) at human-relevant dosages on development, physiology, and social and anxiety-related behaviors later in life, and the consequences of a second juvenile "hit" following prenatal treatment. We exposed male and female Sprague-Dawley rats to PCBs (Aroclor 1221, 1mg/kg/day, ip injection) and/or vehicle during prenatal development (embryonic days 16, 18, 20), juvenile development (postnatal days 24, 26, 28), or both. These exposures had differential effects on behaviors in sex and age-dependent ways; while prenatal exposure had more effects than juvenile, juvenile exposure often modified or unmasked the effects of the first hit. Additionally, females exhibited altered social and anxiety behavior in adolescence, while males displayed small but significant changes in sociosexual preferences in adulthood. Thus, the brain continues to be sensitive to organizing effects of EDCs through juvenile development. As humans are exposed to EDCs throughout multiple periods in their life, these findings have implications for our understanding of EDC effects on physiology and behavior.
authors.affiliation: Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Margaret R
authors.initials: MR
authors.lastname: Bell
authors.affiliation: Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Lindsay M
authors.initials: LM
authors.lastname: Thompson
authors.affiliation: Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA; Franklin College, Franklin, IN 46131, USA.
authors.forename: Karla
authors.initials: K
authors.lastname: Rodriguez
authors.affiliation: Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA; Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA. Electronic address: andrea.gore@austin.utexas.edu.
authors.forename: Andrea C
authors.initials: AC
authors.lastname: Gore
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000818:Animals; D001007:Anxiety / Q000139:chemically induced*; D001140:Aroclors / Q000008:administration & dosage / Q000009:adverse effects; D001522:Behavior, Animal / Q000187:drug effects*; D052244:Endocrine Disruptors / Q000008:administration & dosage / Q000009:adverse effects*; D004785:Environmental Pollutants / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D011078:Polychlorinated Biphenyls / Q000008:administration & dosage / Q000009:adverse effects*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012725:Sexual Behavior / Q000187:drug effects*; D012919:Social Behavior
chemical_list: D001140:Aroclors; D052244:Endocrine Disruptors; D004785:Environmental Pollutants; C032739:aroclor 1221; D011078:Polychlorinated Biphenyls
keywords: Adolescence; Anxiety; Aroclor 1221; Endocrine-disrupting chemical; PCB; Social behavior; Ultrasonic vocalization