title: Gene expression and immunolocalization of fibroblast growth factor 2 in the ovary and its effect on the in vitro culture of caprine preantral ovarian follicles.
abstract: This study quantified Fibroblast growth factor 2 (FGF-2) mRNA and localized FGF-2 protein in different categories of follicles isolated from goat ovaries. In addition, we verified the effects of this factor on the in vitro culture of preantral follicles isolated from goats. For mRNA quantification, we performed real-time PCR using primordial, primary and secondary follicles, as well as cumulus-oocyte complexes (COCs) and mural granulosa and theca cells of small and large antral follicles. For FGF-2 protein localization, the ovaries were subjected to conventional immunohistochemical procedures. Preantral follicles were isolated and cultured in vitro for 12 days in either control (basic) or supplemented with FGF-2 medium. The expression of FGF-2 mRNA was detected in all categories of follicles and there was no difference in preantral follicles and COCs or granulosa/theca cells from small and large antral follicles. However, in large antral follicles, COCs showed expression levels significantly lower than in granulosa/theca cells (p < 0.05). We observed moderate expression of FGF-2 protein in preantral follicles but not in granulosa cells of primordial follicles and theca cells of secondary follicles. In both small and large antral follicles, strong, moderate and weak staining was observed in oocytes, granulosa and theca cells, respectively. The addition of FGF-2 caused a significant increase in the daily follicular growth rate compared to the control group. We conclude that FGF-2 mRNA is expressed throughout follicular development and that its protein can be found in different patterns in preantral and antral follicles. Furthermore, FGF-2 increases the follicular growth rate in vitro.
authors.affiliation: Faculty of Veterinary, State University of Ceará, Fortaleza, CE, Brazil. anderson_almeida@click21.com.br
authors.forename: A P
authors.initials: AP
authors.lastname: Almeida
authors.forename: M V A
authors.initials: MV
authors.lastname: Saraiva
authors.forename: J G
authors.initials: JG
authors.lastname: Alves Filho
authors.forename: G M
authors.initials: GM
authors.lastname: Silva
authors.forename: R F B
authors.initials: RF
authors.lastname: Gonçalves
authors.forename: I R
authors.initials: IR
authors.lastname: Brito
authors.forename: A W B
authors.initials: AW
authors.lastname: Silva
authors.forename: A K F
authors.initials: AK
authors.lastname: Lima
authors.forename: R M S
authors.initials: RM
authors.lastname: Cunha
authors.forename: J R V
authors.initials: JR
authors.lastname: Silva
authors.forename: J R
authors.initials: JR
authors.lastname: Figueiredo
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003470:Culture Media; D054885:Cumulus Cells / Q000502:physiology; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000032:analysis / Q000235:genetics* / Q000494:pharmacology*; D015870:Gene Expression; D006041:Goats; D007150:Immunohistochemistry; D006080:Ovarian Follicle / Q000737:chemistry / Q000187:drug effects / Q000502:physiology*; D010053:Ovary / Q000737:chemistry*; D012333:RNA, Messenger / Q000032:analysis; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary
chemical_list: D003470:Culture Media; D012333:RNA, Messenger; D016222:Fibroblast Growth Factor 2