We have investigated the role of mu- and kappa-opioid receptors in the central control of preovulatory LH and FSH release in the proestrous rat. Animals were anesthetized with chloral hydrate at 14:00 h on proestrus day. Following femoral artery cannulation, they were mounted in a stereotaxic apparatus. Morphine and U-50488H (benzene-acetamide methane sulphonate) were infused intracerebroventri...

BACKGROUND Constitutional delay of growth and puberty (CDGP) is a variation of the onset and timing of pubertal development without a defined endocrine abnormality. Recently published studies indicate that leptin and ghrelin play a role in puberty initiation and progress. They have been implicated in regulation of GnRH secretion, with ghrelin having inhibitory and leptin, facilitatory effects. ...

The asynchronous secretion of gonadotrope LH and FSH under the control of GnRH is crucial for ovarian cyclicity but the underlying mechanism is not fully resolved. Because prostaglandins (PG) are autocrine regulators in many tissues, we determined whether they have this role in gonadotropes. We first demonstrated that GnRH stimulates PG synthesis by induction of cyclooxygenase-2, via the protei...

The ability of equine luteinizing hormone (eLH) to promote follicular growth and maturation in hypophysectomized rats has been assessed. A single injection of equine LH has been shown to promote the growth of a large number of antral and preovulatory follicles. In addition, equine LH markedly increased serum estrogen levels and uterine weight. Furthermore, equine LH, like equine chorionic gonad...

In the normal human menstrual cycle, the final phase of ovarian folliculogenesis leading upto the pre-ovulatory stage is gonadotropin dependent. Luteinising hormone (LH) acts synergistically with follicle stimulating hormone (FSH) to achieve follicular steroidogenesis, luteinisation and ovulation. It therefore follows that the maturational process of the oocyte contained within the follicle and...

BACKGROUND Hypotension and reduced cerebral blood flow secondary to brachiocephalic occlusion (BCO) stimulate various homeostatic physiological and endocrine responses. Our previous studies have also suggested a role of estradiol in augmenting the fetal stress response to BCO. OBJECTIVES We tested the hypothesis that gonadotropins and/or prolactin (PRL) are upregulated in fetal pituitary in r...

BACKGROUND This study compared rates of pregnancy and in vitro fertilization (IVF) parameters in subjects stimulated with follicle stimulating hormone (FSH) plus either recombinant human luteinizing hormone (r-LH) or human menopausal gonadotropin (hMG) in a long gonadotropin releasing hormone (GnRH) agonist IVF protocol. MATERIALS AND METHODS This cohort study enrolled patients who underwent ...

Serum FSH and LH levels in 104 patients with disorders of sexual development were determined by radioimmunoassay and compared with serum FSH and LH levels in 164 normal individuals. 32 of 35 gonadal dysgenesis patients (ages 4.8-18.9 yr) had serum FSH levels which were elevated above the range of normal for chronological age, and 19 had serum LH levels similarly elevated. All patients with elev...

In the normal human menstrual cycle, the final phase of ovarian folliculogenesis leading upto the pre-ovulatory stage is gonadotropin dependent. Luteinising hormone (LH) acts synergistically with follicle stimulating hormone (FSH) to achieve follicular steroidogenesis, luteinisation and ovulation. It therefore follows that the maturational process of the oocyte contained within the follicle and...

Synthetic luteinizing hormone/follicle stimulating hormone-releasing hormone (LH/FSH-RH) (50 mug) was given intravenously to six women with oligomenorrhoea and to four women with secondary amenorrhoea. Peripheral venous blood was withdrawn at regular intervals over a 24-hour period. The concentrations of LH, FSH, and oestradiol-17beta were determined by radioimmunoassay. In all subjects there w...