Objective The inhibitory effects of Morphine and the stimulatory influence of kisspeptin signaling have been demonstrated on GnRH/LH release. Hypothalamic kisspeptin is involved in relaying the environmental and metabolic information to reproductive axis. In the present study the role of kisspeptin/GPR54 signaling system was investigated on relaying the inhibitory effects of morphine on LH horm...

Kisspeptin is the peptide product of the KiSS-1 gene and the endogenous agonist for the GPR54 receptor. Recent evidence suggests the kisspeptin/GPR54 system is a key regulator of the reproductive system. We examined the effect of intracerebroventricular (i.c.v.) and peripheral administration of the active kisspeptin fragment, kisspeptin-10, on circulating gonadotrophins and total testosterone l...

Kisspeptin is a potent stimulator of GnRH secretion that has been implicated in the feedback actions of ovarian steroids. In ewes, the majority of hypothalamic kisspeptin neurons are found in the arcuate nucleus (ARC), with a smaller population located in the preoptic area. Most arcuate kisspeptin neurons express estrogen receptor-alpha, as do a set of arcuate neurons that contain both dynorphi...

Kisspeptin, the product of the KiSS-1 gene, inhibits metastasis and stimulates the hypothalamo-pituitary-gonadal axis. Kisspeptin is therefore a putative target in the treatment of hormone-sensitive malignancies. Prostatic carcinoma remains a significant cause of mortality despite improvements in therapy. The role of kisspeptin in prostatic carcinoma remains undefined. We therefore aimed to inv...

The G protein-coupled receptor 54 (GPR54) and its endogenous ligand, kisspeptin, are essential for activation and regulation of the hypothalamic-pituitary-gonadal axis. Analysis of RNA extracts from individually identified hypothalamic GnRH neurons with primers for GnRH, kisspeptin-1, and GPR54 revealed expression of all three gene products. Also, constitutive and GnRH agonist-induced biolumine...

The neuropeptide kisspeptin plays an important role in fertility and the onset of puberty, stimulating gonadotropin-releasing hormone (GnRH) neurons to activate the hypothalamic-pituitary-gonadal axis. Several studies have demonstrated a morphological interaction between kisspeptin- and GnRH-expressing neurons; however, few have addressed the interaction of kisspeptin with other neuronal subtyp...

Kisspeptin is a peptide that has been implicated in the regulation of GnRH cells in the brain. Immunohistochemical studies were undertaken to examine the distribution of kisspeptin-immunoreactive (IR) cells in the ovine diencephalon and determine the effect of ovariectomy in the ewe. We report that kisspeptin colocalizes to a high proportion of GnRH-IR cells in the preoptic area, which is a nov...

Central precocious puberty (CPP) is caused by premature activation of hypothalamic gonadotropin-releasing hormone (GnRH) secretion. Kisspeptin and G-protein coupled receptor-54 system is the essential gatekeeper of the reproductive system, playing a key role in the activation of the gonadotropic axis at puberty. We aimed to determine whether serum kisspeptin may function as a marker for CPP by ...

Kisspeptin is vital for the neuroendocrine regulation of GNRH secretion. Kisspeptin neurons are now recognized as a central pathway responsible for conveying key homeostatic information to GNRH neurons. This pathway is likely to mediate the well-established link between energy balance and reproductive function. Thus, in states of severely altered energy balance (either negative or positive), fe...

BACKGROUND Kisspeptin and naloxone stimulate the reproductive axis while morphine inhibits its function. We have investigated the effect of central injection of kisspeptin-10 on mean plasma testosterone concentration in morphine or naloxone pretreated rats. MATERIALS AND METHODS In this experimental study, 60 male Wistar rats that were divid- ed into 12 groups (n=5 per group) received saline,...