The ovarian follicle is a major site of steroidogenesis, crucially required for normal ovarian function and female reproduction. Our understanding of androgen synthesis and metabolism in the developing follicle has been limited by the sensitivity and specificity issues of previously used assays. Here we used liquid chromatography-tandem mass spectrometry to map the stage-dependent endogenous st...

In the brachiopod Terebratalia transversa, each ovarian follicle consists of (i) a prophase-arrested oocyte with an enlarged nucleus (= the germinal vesicle, or GV), and (ii) a surrounding sheath of follicle cells that attach to the oocyte by means of junctional complexes. Within about 80 min after removing a follicle from the ovary, the follicular sheath undergoes a microfilament-mediated retr...

By using enzyme immunoassay techniques we have quantified the ovarian ecdysteroids during the 7-day cycle of olicyte maturation in Blattella germanica. Immunoreactive ecdysteroid levels were low on days O-2, increased to higher values on days 3-6, and peaked on day 7 (about 5 ng of 20-hydroxyecdysone equivalents per pair of ovaries). The predominant non-conjugated ovarian ecdysteroid detected b...

Background: The fibroblast growth factors (FGF-4) are a group of heparin-binding single chain polypeptides that play a pivotal role in development, cell growth, tissue repairing and transformation. The aim of this study is to improve development and maturation outcome of vitrified mouse pre-antral follicle by adding of fibroblast growth factor (FGF) into medium culture. Materials and Methods: P...

background: the ultrastructural analysis of cultured follicles could direct us to understand subcellular changes during in vitro culture. objective: this study was done to verify the ultrastructural characteristics of in vitro cultured mouse isolated preantral follicles in co-culture system in the presence and absence of leukemia inhibitory factor (lif) materials and methods: mechanically isola...

background: leukemia inhibitory factor (lif) is a pleiotropic cytokine of interleukin-6 family with a remarkable range of biological actions such as proliferative effects on the granulosa and theca cells. the aim of this study was to evaluate the effects of lif on the growth and maturation of mouse fresh and vitrified preantral follicles, an in vitro model was developed. methods: the ovaries of...

Consisting of Kit ligand and receptor Kit, the Kit system is involved in regulating many ovarian functions such as follicle activation, granulosa cell proliferation, and oocyte growth and maturation. In mammals, Kit ligand is derived from the granulosa cells and Kit receptor is expressed in the oocyte and theca cells. In the zebrafish, the Kit system contains two ligands (Kitlga and Kitlgb) and...

Background: Leukemia inhibitory factor (LIF) is a pleiotropic cytokine of interleukin-6 family with a remarkable range of biological actions such as proliferative effects on the granulosa and theca cells. The aim of this study was to evaluate the effects of LIF on the growth and maturation of mouse fresh and vitrified preantral follicles, an in vitro model was developed. Methods: The ovaries of...

Background: Cryopreservation of oocytes is an effective technology in assisted reproductive technology. Although successful vitrification of gametes has been reported in several mammalian species, the survival is generally low. The aim of this study was to investigate the effects of fibroblast growth factor (FGF) and hepatocyte growth factor (HGF) on preantral follicle development after vitrifi...