It is well established that GnRH can stimulate the release of LH and FSH in mammals. Two GnRHs have been found in the chicken hypothalamus, cGnRH-I and -II. There is controversy as to whether either peptide can stimulate release of FSH in birds. The present studies compared the ability of cGnRH-I and -II to stimulate the release of FSH and LH in chickens. Lamprey (l) GnRH-III may be a specific-...

Many studies have shown that cyclic adenosine-5'-monophosphate (cAMP)-dependent protein kinase A (PKA) and G-protein-coupled receptor 3 (GPR3) are crucial for controlling meiotic arrest in oocytes. However, it is unclear how gonadotropins modulate these factors to regulate oocyte maturation, especially by gap junctional communication (GJC). Using an in vitro meiosis-arrested mouse cumulus-oocyt...

OBJECTIVE The objectives of this study were to observe the changes in follicle-stimulating hormone (FSH) and bone mineral density (BMD) in postmenopausal women, to research the relationship between FSH and postmenopausal osteoporosis, and to observe the effects of FSH on osteoclast differentiation in RAW264.7 cells. METHODS We analyzed 248 postmenopausal women with normal bone metabolism. A r...

OBJECTIVE The purpose of the present study was to evaluate the hormonal profile of patients of postmenopausal age during estrogen replacement therapy (ERT) with special reference to the serum levels of biologically active FSH (B-FSH) in a self-adjusted ERT model. DESIGN The hormonal values found have been correlated to climateric symptoms reported by the patients (scored by the Kupperman meno...

Understanding the mechanisms regulating oocyte developmental competence is essential to enhance the clinical efficiency of assisted reproduction. FSH orchestrates the acquisition of oocyte competence, both in vivo and in vitro. Multiple pathways are implicated in FSH signalling; however, their precise coordination remains unresolved. A robust system to investigate FSH signalling is oocyte in vi...

The final number of Sertoli cells reached during the proliferative periods determines sperm production capacity in adulthood. It is well known that FSH is the major Sertoli cell mitogen; however, little is known about the signal transduction pathways that regulate the proliferation of Sertoli cells. The hypothesis of this investigation was that FSH regulates proliferation through a PI3K/Akt/mTO...

The FSH molecular mechanism of action is best recognized for its stimulation of the adenylyl cyclase/cAMP pathway via activation of a G protein. Recently, links between cAMP, phosphatidylinositol 3-kinase (PI3K) and protein kinase B (PKB) signaling pathways in thyroid and granulosa cells have been observed. The aim of this study was to investigate the possible role of the PI3K/PKB pathway in FS...

PURPOSE To compare the embryo outcomes of in vitro fertilization/intra-cytoplasmic sperm injection with a gonadotropin-releasing hormone (GnRH) antagonist protocol with follicle stimulating hormone (FSH) and with human menopausal gonadotropin (hMG). METHODS We performed a retrospective cohort study in 465 patients. Stimulation was started by daily FSH injection, and either FSH was continued (...

Follicle-stimulating hormone (FSH) is the pituitary hormone responsible for testicular tubal development and ovarian follicular recruitment and maturation. Both recombinant and purified urinary FSH are currently used for ovulation induction in women undergoing assisted reproduction. In this report, we describe Chinese hamster ovary (CHO-K1) cell expression of a novel long-acting human FSH singl...

The effects of PMSG on the mitotic activity of granulosa cells and atresia of large folicles in 24-day-old rats were examined. The results showed that the labelling index (1) decreased in atretic follicles parallel with a loss of FSH binding, and (2) increased in hypophysectomized rats treated with FSH. It is concluded that FSH stimulates granulosa cell divisions and that atresia may be caused ...