introduction: gonadotropin inhibitory hormone (gnih) has been known as a key inhibitor of the secretion of gonadotropin releasing hormone (gnrh). ewe has estrous cycles comprising of follicular and luteal phases. follicular phase is in turn divided into proestrous and estrous phases. blood level of lh increases in follicular and decreases in luteal phases. the aim of the present study was to ev...

introduction: gonadotropin inhibitory hormone (gnih) is believed to be an inhibitor of gonadotropin releasing hormone (gnrh) secretion. the role of gnih in lactational inhibition of gonadotropin secretion is not well known therefore, the aim of the present study was to evaluate the effect of lactation on expression of gnih in these nuclei of lactating and non-lactating rats. methods: ten postpa...

introduction: gonadotropin inhibitory hormone (gnih) and agouti-related peptide (agrp) are orexigenic peptides expressed in the arcuate nucleus (arc) of the hypothalamus in the ewe. in addition, effects of gnih and agrp on the regulation of gonadotropin releasing hormone secretion have been shown in some mammals. the objective of the present study was to investigate the coexpression of gnih and...

until 2000 it was believed that gonadotropin-releasing hormone (gnrh) was the sole regulator of hypophyseal gonadotropes. in 2000, the discovery of a gonadotropin inhibitory hormone (gnih) initiated a revolution in the field of reproductive physiology. identification of gnih homologues in mammals, the arginine-phenylalanine- amide (rfamide)-related peptides (rfrps), indicated a similar function...

Until 2000 it was believed that gonadotropin-releasing hormone (GnRH) was the sole regulator of hypophyseal gonadotropes. In 2000, the discovery of a gonadotropin inhibitory hormone (GnIH) initiated a revolution in the field of reproductive physiology. Identification of GnIH homologues in mammals, the arginine-phenylalanine- amide (RFamide)-related peptides (RFRPs), indicated a similar function...

Gonadotropin-releasing hormone in Cyprinidae as in other Vertebrates functions as a brain signal which stimulates the secretion of luteinizing hormone from the pituitary gland. Two forms of gonadotropin-releasing hormone have been identified in cyprinids, chicken gonadotropin-releasing hormone II and salmon gonadotropinreleasing hormone. Hypohysiotropic functions are fulfilled mainly by salmon ...

Gonadotropin-releasing hormone (GnRH) regulates secretion of both of the gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone. Thus, it is a key hormone for vertebrate reproduction. GnRH was considered to be unusual among hypothalamic neuropeptides in that it appeared to have no direct antagonist, although some neurochemicals and peripheral hormones (opiates, GABA, gonadal s...

Physical and psychological stressors suppress hypothalamic-pituitary-gonadal axis activity and sexual behavior and consequently induce reproductive dysfunction. Recently, it has been shown that gonadotropin-inhibitory hormone (GnIH), also called RFamide-related peptide 3 (RFRP) in mammals, which is a potent inhibitory regulator of gonadotropin-releasing hormone (GnRH) and gonadotropin, is invol...

Gonadotropin-inhibitory hormone (GnIH) acts as a negative regulator of reproduction by acting on gonadotropes and gonadotropin-releasing hormone (GnRH) neurons. Despite its functional significance, the molecular mechanism of GnIH action in the target cells has not been fully elucidated. To expand our previous study on GnIH actions in gonadotropes, we investigated the potential signal transducti...