Influence of FSH and hCG on the resumption of meiosis of bovine oocytes surrounded by cumulus cells connected to membrana granulosa

摘要: Cumulus oocyte complexes (COCs) and cumulus connected to a piece of the membrane granulosa (COCGs) were isolated from bovine antral follicles with diameter 2 8 mm. After culture COCGs without gonadotrophic hormones for 22 hr approximately 50% oocytes still in germinal vesicle (GV) stage. Histology showed that pieces membrana free thecal cells parts basal membrane. This indicates solely inhibits progression meiosis. To investigate effect gonadotropins on resumption meiosis small medium sized follicles, COCs cultured or rec-hFSH hCG. Addition 0.05 IU resulted breakdown 97.8% compared 46% control group, an increase (479 microns vs. 240 group). hCG had no nuclear maturation (47.2% GV 48.5% group) nor expansion (246 RT-PCR cDNA follicular wall, cells, COCs, revealed mRNA FSH receptor was present all cell types except oocytes. LH detected exclusively cells. Nucleotide sequence analysis alignment cloned PCR products presence two isoforms mRNA. It is concluded that, vitro, oocytes, originating meiotically arrested by granulosa, triggered not LH. supported fact receptors FSH, but LH, are transcribed these follicles.