Gonadotrophin-inhibitory hormone (GnIH) is a novel hypothalamic neuropeptide that was discovered in birds as an inhibitory factor for gonadotrophin release. RFamide-related peptide (RFRP) is a mammalian GnIH orthologue that inhibits gonadotrophin synthesis and release in mammals through actions on gonadotrophin-releasing hormone (GnRH) neurones and gonadotrophs, mediated via the GnIH receptor (...

We have previously shown that administration of antiprogestin (AP) type II RU486 to ovariectomized (OVX) rats on the morning of pro-oestrus decreases the magnitude of preovulatory gonadotrophin surge. This suggests that the effect of RU486 on LHRH-dependent gonadotrophin release may be independent of its ability to block progesterone actions. The aim of the present research was to study the pos...

In the absence of specific dose equivalency data, the aim of this study was to compare the clinical results during the cross-over from menopausal urinary products (human menopausal gonadotrophin; HMG) to recombinant follicle stimulating hormone (FSH) follitrophin beta (FSHr) in order to determine whether the manufacturer's recommendation for equivalence of ampoule to ampoule (50 IU FSHr:75 IU H...

Fifty women with polycystic ovaries took part in a prospective randomized study. All women required treatment by in-vitro fertilization (IVF) for reasons other than anovulation. They had all previously undergone ovarian stimulation with gonadotrophin therapy which had failed to result in pregnancy or had been abandoned due to high risk of developing ovarian hyperstimulation syndrome (OHSS). Twe...

This study was conducted to investigate the possible role of angiogenin in the pathogenesis of ovarian hyperstimulation syndrome (OHSS). The study group consisted of 10 healthy women who developed severe OHSS (group A) following ovarian stimulation by a long protocol of gonadotrophin-releasing hormone analogues/human menopausal gonadotrophin for in-vitro fertilization. A control group B (n = 10...

The aim of this study was to enhance the ovulation and subsequent embryo production of equine chorionic gonadotrophin (eCG) superovulated goats by supplementing with human chorionic gonadotrophin (hCG) or gonadotrophin releasing hormone (GnRH). Thirty crossbred donor does were oestrus synchronized using controlled internal drug release (CIDR) device and superovulated using 1500 IU eCG. Then all...

Ovulation rate, fertilization rate and prenatal mortality were studied in yearling beef heifers treated with PMSG or FSH and in non-treated controls. Oestrus was synchronized in 50% of the animals in each treatment with an oral progestagen. The gonadotrophin injections were given during the normal oestrous cycle or during the progestagen-administration period. All heifers were inseminated 6 to ...

The role of transvaginal pulsed colour Doppler ultrasound in the assessment of ovarian vascularity was studied in 196 in-vitro fertilization (IVF) cycles. The changes in ovarian blood flow after gonadotrophin-releasing hormone agonist (GnRHa) down-regulation and human menopausal gonadotrophin (HMG) stimulation were determined. The data obtained showed that the ovarian blood flow was significant...

BACKGROUND Reproductive function following cancer treatment is of increasing importance with improving survival rates. We therefore assessed the markers of the ovarian reserve in premenopausal women, to investigate and compare the effects of chemotherapy and long-term gonadotrophin withdrawal on ovarian function. METHODS Fifty premenopausal (age range 28-52 years) women with early breast canc...

To investigate the effects of alterations in GnRH pulse frequency on gonadotrophin secretion, we administered low dose GnRH pulses (25 ng/kg) at hourly or 2-hourly frequencies to eight normal men. All subjects received GnRH pulses i.v. every 2 h for 88 h. Following this, exogenous GnRH was discontinued in four normal men (Group A, GnRH withdrawal), and the frequency of GnRH injections was incre...