Reproduction Abstracts

Oocytes are arrested in prophase I until the LH surge, which stimulates an EGF-like growth factor signaling cascade critical for cumulus expansion, and releases meiotic arrest while inhibiting the expression of natriuretic peptide C (NPPC). In rodents, there is evidence that KIT ligand (KITLG) secreted from granulosa/cumulus cells may also enhance nuclear maturation of the oocyte. The objective of the present study was to measure the expression of KITLG in bovine cumulus–...

The evolutionarily conserved Wnt/β-catenin signal transduction pathway controls many biological processes. The objective of this study was to determine the role of this signaling pathway in follicular development and luteal function. To this purpose PMSG–eCG gonadotropin-prepubertal treated female rats were injected with a Wnt inhibitor (XAV939, 5 μg/ovary, Wnt-I group) or vehicle (DMSO, control group) into the bursa of both ovaries the day of hCG administration...

Premature ovarian failure (POF) affects around 1% of women and is idiopathic in 74–90% of cases. Our mouse model of POF, the double mutant (DM), are fertile at 6-weeks and undergo POF by 3-months consistent with a decline in developing follicles. However, DM ovaries have increased numbers of primary follicles at the 3a stage, indicating a block in follicle development.We investigated whether we could rescue the ability of DM oocytes at 3- and 9-week...

The onset of mammalian follicle development is marked by granulosa cell (GC) proliferation, GC shape change, and oocyte growth. Despite their critical role in female fertility the factors and mechanisms underlying these cellular changes remain largely unknown. The transforming growth factor beta (TGFβ) superfamily has been strongly implicated in early follicle growth. Disruption of the function or expression of members of the TGFβ superfamily, receptors or key compon...

The oocyte influences hormonal and cellular changes in the follicle and the ovary. Theca cells, surrounding the follicle basement membrane, synthesise androgen and thus regulate ovarian oestrogen production. The vascular theca layer provides nutrients to the avascular inner follicle. In C1galt1 mutant mice, all oocytes lack core 1-derived O-glycans due to oocyte-specific ablation of core 1 beta 1,3-galactosyltransferase. C1galt1 mutants have increase...