title: Immunoreactive TSH cells in juvenile and peripubertal rats after estradiol and human chorionic gonadotropin treatment.
abstract: Different hormones and growth factors control the homeostasis of the anterior pituitary gland. We examined the morphological features of pituitary thyroid stimulating hormone (TSH)-producing cells in juvenile and peripubertal female rats after treatments with estradiol-dipropionate (EDP), human chorionic gonadotropin (hCG) and a combination of both hormones (EDP+hCG). TSH-producing cells were labelled using a peroxidase-antiperoxidase immunohistochemical procedure for binding of a rabbit anti-rat beta-thyrotropic polyclonal antisera. Morphometric differences in the cytoplasmic and nuclear volume densities in thyrotropes after the treatments were determined using a stereological method. The relative weights of the pituitary glands were significantly higher in the EDP- and EDP+hCG-treated juvenile and peripubertal rats than in untreated age-matched controls. Treatment with EDP promoted a decrease, and treatment with hCG an increase, of the cellular and nuclear volumes in TSH cells in both juvenile and peripubertal females in comparison with the respective controls. Treatment with a combination of EDP+hCG did not induce any significant changes. The cytoplasmic and nuclear volume densities in TSH cells in the EDP+hCG-treated group were significantly higher than in the EDP-treated, and significantly lower than in hCG-treated rats at both growth stages. These findings suggest that estradiol and hCG exerted opposite effects on pituitary TSH-immunoreactive cells. The observed effects on thyrotrope morphology were apparently independent of the stage of development.
authors.affiliation: Institute for Biological Research Sinisa Stanković, Despota Stefana 142, 11060 Belgrade, Serbia and Montenegro. sekmic@ibiss.bg.ac.yu
authors.forename: Milka
authors.initials: M
authors.lastname: Sekulić
authors.forename: Branka
authors.initials: B
authors.lastname: Sosić-Jurjević
authors.forename: Branko
authors.initials: B
authors.lastname: Filipović
authors.forename: Milica
authors.initials: M
authors.lastname: Manojlović-Stojanoski
authors.forename: Verica
authors.initials: V
authors.lastname: Milosević
mesh_terms: D000818:Animals; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D005260:Female; D007150:Immunohistochemistry; D009929:Organ Size / Q000187:drug effects; D010903:Pituitary Gland, Anterior / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013972:Thyrotropin / Q000378:metabolism*
chemical_list: D006063:Chorionic Gonadotropin; D004958:Estradiol; D013972:Thyrotropin; C023482:estradiol dipropionate