title: In utero and lactational exposure to PCB 118 and PCB 153 alter ovarian follicular dynamics and GnRH-induced luteinizing hormone secretion in female lambs.
abstract: The effects of in utero and lactational exposure to two structurally different polychlorinated biphenyl (PCB) congeners on follicular dynamics and the pituitary-gonadal axis in female lambs were investigated. Pregnant ewes received corn oil, PCB 118, or PCB 153, and offspring was maintained until 60 days postpartum. Ovarian follicles were quantified using stereology. Plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured using radioimmunoassay before and after administration of a gonadotropin releasing hormone (GnRH) analog. PCB 118 exposure increased numbers of transitional, secondary, and the sum of secondary, early antral, and antral (Σsecondary-antral) follicles, PCB 153 exposure only increased the number of primary follicles. GnRH-induced LH levels were significantly elevated in the PCB 153 exposure group. We conclude that PCB 153 and PCB 118 alter follicular dynamics in lambs and modulate the responsiveness of the pituitary gland to GnRH.
authors.affiliation: Department of Production Animal Sciences, Norwegian School of Veterinary Science, Postboks 8146 Dep., N-0033 Oslo, Norway. marianne.kraugerud@nvh.no
authors.forename: Marianne
authors.initials: M
authors.lastname: Kraugerud
authors.forename: Mona
authors.initials: M
authors.lastname: Aleksandersen
authors.forename: Jens Randel
authors.initials: JR
authors.lastname: Nyengaard
authors.forename: Gunn C
authors.initials: GC
authors.lastname: Ostby
authors.forename: Arno C
authors.initials: AC
authors.lastname: Gutleb
authors.forename: Ellen
authors.initials: E
authors.lastname: Dahl
authors.forename: Vidar
authors.initials: V
authors.lastname: Berg
authors.forename: Wenche
authors.initials: W
authors.lastname: Farstad
authors.forename: Tore
authors.initials: T
authors.lastname: Schweder
authors.forename: Janneche U
authors.initials: JU
authors.lastname: Skaare
authors.forename: Erik
authors.initials: E
authors.lastname: Ropstad
mesh_terms: D000818:Animals; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism*; D006080:Ovarian Follicle / Q000187:drug effects*; D010902:Pituitary Gland / Q000187:drug effects; D011078:Polychlorinated Biphenyls / Q000633:toxicity*; D011247:Pregnancy; D012756:Sheep
chemical_list: C070055:2,3',4,4',5-pentachlorobiphenyl; D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D011078:Polychlorinated Biphenyls; C014024:2,4,5,2',4',5'-hexachlorobiphenyl