Gonadotropin-releasing hormone (GnRH) is the ultimate output signal of an intricate network of neuroendocrine factors that, acting on the pituitary, trigger gonadotropin release. In turn, gonadotropins exert their trophic action on the gonads to stimulate the synthesis of sex steroids thus completing the gonadotropic axis through feedback regulatory mechanisms of GnRH release. These feedback lo...

Nistala, Ravi, Xiaoji Zhang, and Curt D. Sigmund. Differential expression of the closely linked KISS1, REN, and FLJ10761 genes in transgenic mice. Physiol Genomics 17: 4–10, 2004. First published January 6, 2004; 10.1152/physiolgenomics.00205.2003.—We previously reported the development and characterization of transgenic mice containing a large 160-kb P1 artificial chromosome (PAC) encompassing...

In mammals, lactation suppresses GnRH/LH secretion resulting in transient infertility. In rats, GnRH/LH secretion is rescued within 18-48 h after pup separation (PS) and rapidly re-suppressed by subsequent re-exposure of pups. To elucidate the mechanisms underlying these rapid modulations, changes in the expression of kisspeptin, a stimulator of GnRH secretion, in several lactating conditions (...

The Kiss1 gene encodes a family of peptides called kisspeptins, which bind to the G protein-coupled receptor GPR54. Kisspeptin(s) and its receptor are expressed in the forebrain, and the discovery that mice and humans lacking a functional GPR54 fail to undergo puberty and exhibit hypogonadotropic hypogonadism implies that kisspeptin signaling plays an essential role in reproduction. Studies in ...

Pubertal onset only occurs in a favorable, anabolic hormonal environment. The neuropeptide kisspeptin, encoded by the Kiss1 gene, modifies GnRH neuronal activity to initiate puberty and maintain fertility, but the factors that regulate Kiss1 neurons and permit pubertal maturation remain to be clarified. The anabolic factor insulin may signal nutritional status to these neurons. To determine whe...

OBJECTIVE Stress is known to be an inhibitor of the reproductive hypothalamic-pituitary-gonadal (HPG) axis. However, the neural and molecular connections between stress and reproduction are not yet understood. It is well established that in both humans and rodents, kisspeptin (encoded by the kiss1 gene) is a strong stimulator of the HPG axis. In the present study we hypothesized that endocannab...

The adipocyte-derived hormone leptin is required for normal pubertal maturation in mice and humans and, therefore, leptin has been recognized as a crucial metabolic cue linking energy stores and the onset of puberty. Several lines of evidence have suggested that leptin acts via kisspeptin expressing neurons of the arcuate nucleus to exert its effects. Using conditional knockout mice, we have pr...

Kisspeptin (KISS1) and its receptor (KISS1r) are essential for normal reproductive function in many species, but the role of kiss1/kiss1r signalling in the dog has not yet been elucidated. The aims of this study were to identify the canine kiss1 and kiss1r genes and to determine gonadotrophin and oestradiol stimulatory activity of KP-10, the shortest biologically active form of KISS1. Canine ki...

Trophoblast migration and invasion during pregnancy are under strict physiological control, both temporally and spatially. The trophoblast’s ability to invade the endometrium is regulated by the dynamic interaction between invasion-related genes. Once this dynamic balance is broken, the trophoblast exhibits abnormal invasion ability, often resulting in recurrent spontaneous abortion (RSA). Kiss...

BACKGROUND Female reproductive health is noticeably compromised by obesity. The underlying mechanisms remain to be elucidated. Accumulating evidence indicates that the expression level of ovarian Kiss1 peaks in the afternoon during prooestrus, suggesting local regulatory roles for Kiss1 in the ovulatory process. We used a diet-induced model of obesity to evaluate whether the ovarian Kiss1 syste...