Mast cells occur in the brain and their number changes with reproductive status. While it has been suggested that brain mast cells contain the mammalian hypothalamic form of gonadotropin-releasing hormone (GnRH-I), it is not known whether mast cells synthesize GnRH-I de novo. In the present study, mast cells in the rat thalamus were immunoreactive to antisera generated against GnRH-I and the Gn...

Gonadotrophin-releasing hormone (GnRH) neurones located within the brain are the final neuroendocrine output regulating the reproductive hormone axis. Their small number and scattered distribution in the hypothalamus make them particularly difficult to study in vivo. The Cre/loxP system is a valuable tool to delete genes in specific cells and tissues. We report the production of two mouse lines...

Gonadotropin-releasing hormone (GnRH) neurons integrate synaptic information in their dendrites in order to precisely control GnRH secretion and hence fertility. Recent discoveries concerning the structure and function of GnRH neuron dendrites have shed new light on the control of GnRH neuron excitability and GnRH secretion. This work suggests that GnRH neurons have a unique projection to the m...

A functional GnRH receptor (GnRH-R) in the anterior pituitary is critical for normal LH/FSH secretion, pubertal development and reproduction. Inactivating mutations of the GnRH-R have been identified in patients with idiopathic hypogonadotrophic hypogonadism. In this article we summarize phenotypic characteristics of these patients and focus on specific functional alterations of the human GnRH-...

The crucial role of pituitary GnRH receptors (GnRH-R) in the control of reproductive functions is well established. These receptors are the target of GnRH agonists (through receptor desensitization) and antagonists (through receptor blockade) for the treatment of steroid-dependent pathologies, including hormone-dependent tumors. It has also become increasingly clear that GnRH-R are expressed in...

Background: This study aims to verify if luteal estradiol pre-treatment improves IVF/ICSI outcomes in a GnRH antagonist protocol as compared to a micro dose GnRH agonist protocol in poor-responding patients. Materials and Methods: A total of 116 IVF/ICSI cycles were included in this prospective randomized clinical trial. The selected women were randomly assigned to receive an estradiol pre-trea...

Gonadotrophin-releasing hormone (GnRH) regulates gonadotrophin biosynthesis and release in the anterior pituitary via specific receptors. Extrapituitary expression and action of GnRH have been demonstrated in several species. A possible role for GnRH in preimplantation embryonic development, endometrial preparation, and the implantation process has been previously suggested. Moreover, the prese...

background: gnrh agonist administration in the luteal phase has been suggested to beneficially affect the outcome of intracytoplasmic sperm injection (icsi) and embryo transfer (et) cycles. this blind randomized controlled study evaluates the effect of gnrh (gonadotropine releasing hormone) agonist administration on icsi outcome in gnrh antagonist ovarian stimulation protocol in women with 2 or...

In many vertebrates, social interactions regulate reproductive capacity by altering the activity of the hypothalamic-pituitary-gonadal (HPG) axis. To better understand the mechanisms underlying social regulation of reproduction, we investigated the relationship between social status and one main component of the HPG axis: expression levels of gonadotropin-releasing hormone receptor (GnRH-R). So...

In rat anterior pituitary cell cultures GnRH (1nM) stimulated a pro-e increase in LH release into the medium from 1 to 8 h of incubation, while cellular LH showed a corresponding decrease. GnRH (1nM) neither modified the uptake nor the incorporation of [3H]-glucosamine and [3H]-proline into total protein. The incorporation of ["HI-proline into cellular LH also was unaffected by GnRH. In contras...