GABA, the main inhibitory neurotransmitter, acts through GABA(A/C) and GABA(B) receptors (GABA(B)Rs); it is critical for gonadotropin regulation. We studied whether the lack of functional GABA(B)Rs in GABA(B1) knockout (GABA(B1)KO) mice affected the gonadotropin axis physiology. Adult male and female GABA(B1)KO and wild-type (WT) mice were killed to collect blood and tissue samples. Gonadotropi...

Granulosa cells from immature hypophysectomized diethylstilbestrol-treated rats displayed pronounced intracellular and intercellular changes after 48 hr of exposure to follicle-stimulating hormone (FSH) in vitro. As determined by light and electron microscopy, most of the FSH-treated cells became highly aggregated and grew in multilayered clusters. Numerous gap junctions were seen between cells...

Melanocortin- 4 receptor (MC4R) and agouti- related peptide (AgRP) are involved in energy homeostasis in rats. According to MC4R and AgRP effects on luteinizing hormone (LH) secretion, they may influence the estrous cycle of rats. Therefore, the aim of this study was to investigate the expression of MC4R and AgRP mRNAs at different stages of estrous cycle in the rat’s hypothalamus. The estrous ...

The denaturation of chorionic gonadotropin in 40 per cent aqueous urea solution has been found exceptional with respect to both the heat of activation and entropy of activation, but similar to other protein denaturations when compared on the basis of free energy of activation (1). The low rate (2) of inactivation of mare serum gonadotropin in 40 per cent aqueous urea solution at 37.5”, along wi...

Neurosteroids are involved in the regulation of multiple behavioral and physiological processes metabolic activities vertebrate brain. However, central mechanisms how neurosteroid synthesis is regulated far to be understood. Gonadotropin-inhibitory hormone (GNIH) a hypothalamic neuropeptide that negatively regulates gonadotropin secretion but also inhibits sexual aggressive behaviors birds mamm...

The gonadotropin-ovary axis of patients with anorexia nervosa was assessed with the aim of distinguishing between an intrinsically hypophysial deficiency and pituitary malfunction secondary to hypothalamic impairment. The most consistent endocrine abnormality was low serum luteinizing and follicle stimulating hormone (LH and FSH) levels associated with depressed serum estradiol levels. Gonadotr...

.......................................................................................page 10 Chapter One: Evidence for a Role of Luteinizing Hormone in Alzheimer Disease Abstract...............................................................................page 13 Background...........................................................................page 14 Gender Differences in Alzheimer Disea...

Vertebrate gonads are the sites of synthesis and binding of many peptides that were initially classified as neuropeptides. These gonadal neuropeptide systems are neither well understood in isolation, nor in their interactions with other neuropeptide systems. Further, our knowledge of the control of these gonadal neuropeptides by peripheral hormones that bind to the gonads, and which themselves ...

Discoveries of how social behavior can influence the plasticity of gonadotropin-releasing hormone (GnRH) have revolutionized the field of behavioral neuroendocrinology by providing new insights into the neural mechanisms controlling behavior. In 2000, the neuropeptide gonadotropin inhibitory hormone (GnIH) was discovered and is changing the way we view how the brain mediates reproduction and as...

The availability of tools for probing the genome and proteome more efficiently has allowed for the rapid discovery of novel genes and peptides that play important, previously uncharacterized roles in neuroendocrine regulation. In this review, the role of a class of neuropeptides containing the C-terminal Arg-Phe-NH(2) (RFamide) in regulating the reproductive axis will be highlighted. Neuropepti...