title: Reproductive hormones affect follicular cells and ooplasm of Stage I and II oocytes in zebrafish.
abstract: The basic pathway of oocyte development and its regulation is evolutionarily conserved among vertebrates; however, little is known about the role of hormones at the first stages (Stages I and II) of follicle development in fish. In the present study, zebrafish follicles at Stages I and II were exposed in vitro to the reproductive hormones 17β-oestradiol (E2), 11-ketotestosterone (11KT), 17,20β-dihydroxy-4-pregnen-3-one (DHP) and to the secondary messenger dibutyryl cyclic adenosine monophosphate (db-cAMP) at a concentration of 1µM for a 48-h period. Morphological alterations of the ooplasm were assessed by transmission electron microscopy and of the granulosa cell layer by quantitative stereology. Expression of mRNA was analysed for cell-cycle genes (cyclin B and E) and resident proteins of the endoplasmic reticulum (calnexin and 78-kDa glucose-regulated protein (grp78/bip)). E2and db-cAMP stimulated the presence of endoplasmic reticulum in the ooplasm and calnexin mRNA increased in the db-cAMP treatment, but also in response to 11KT and DHP. 11KT, DHP and db-cAMP inhibited the progression of the cell cycle in the granulosa-theca cell layer, indicated by a reduction of the nucleus volume-weighted size of granulosa cells and of increased cyclin E mRNA expression. Reproductive hormones had different effects on the ooplasm and the granulosa-theca cell layer of zebrafish follicles, predominantly at Stage II.
authors.affiliation: CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associated Laboratory, UPorto - University of Porto, Laboratory of Cellular, Molecular and Analytical Studies, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: Maria Lígia
authors.initials: ML
authors.lastname: Sousa
authors.affiliation: ICBAS - Institute of Biomedical Sciences Abel Salazar, UPorto - University of Porto, Laboratory of Histology and Embryology, R. Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Silva
authors.affiliation: CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associated Laboratory, UPorto - University of Porto, Laboratory of Cellular, Molecular and Analytical Studies, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Malhão
authors.affiliation: CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associated Laboratory, UPorto - University of Porto, Laboratory of Cellular, Molecular and Analytical Studies, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Rocha
authors.affiliation: CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associated Laboratory, UPorto - University of Porto, Laboratory of Cellular, Molecular and Analytical Studies, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Rocha
authors.affiliation: CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associated Laboratory, UPorto - University of Porto, Laboratory of Cellular, Molecular and Analytical Studies, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: Ralph
authors.initials: R
authors.lastname: Urbatzka
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004958:Estradiol / Q000494:pharmacology* / Q000502:physiology; D005260:Female; D006107:Granulosa Cells / Q000648:ultrastructure; D006908:Hydroxyprogesterones / Q000494:pharmacology*; D009865:Oocytes / Q000502:physiology*; D006080:Ovarian Follicle / Q000502:physiology*; D013739:Testosterone / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000502:physiology; D015027:Zebrafish
chemical_list: D006908:Hydroxyprogesterones; C007433:17,20-dihydroxy-4-pregnen-3-one; D013739:Testosterone; D004958:Estradiol; C003600:11-ketotestosterone