title: Developmental changes in the role of gonadotropin-inhibitory hormone (GnIH) and its receptors in the reproductive axis of male Xiaomeishan pigs.
abstract: Gonadotropin-inhibitory hormone (GnIH), a key regulator of vertebrate reproduction, was identified in the Japanese quail in 2000, and RFamide-related peptide-3 (RFRP-3) was found to be a mammalian GnIH ortholog. To further determine its role in the reproductive system of male Xiaomeishan pigs, we systematically investigated changes in GnIH and its receptors (GPR147 and GPR74) during the development of the reproductive axis of male pigs. We also investigated the direct effect of RFRP-3 on the synthesis and secretion of testosterone in Leydig cells in vitro. The expression patterns of GnIH in the reproductive axis of male pigs at different stages of development (postnatal 3, 30, 60, 90, and 120D) were studied using semiquantitative RT-PCR and immunohistochemistry. Our results show that hypothalamic, pituitary and testicular levels of GnIH and its receptors mRNA significantly changed on postnatal day 30 and postnatal day 90. The immunoreactivities of the GnIH proteins were mainly localized to the spermatogenic cells, sustentacular cells and interstitial cells of the testis throughout sexual development. It was confirmed that different doses of GnIH/RFRP-3 inhibited the release and synthesis of testosterone, and impacted on the gene expression of 3β-hydroxysteroid dehydrogenase (3β-HSD) and P450, enzymes that play a key role in the synthesis of testosterone. Together, this research provides molecular and morphological data on the regulation of GnIH in the reproductive development of male pigs.
authors: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Lucheng
authors: L
authors: Zheng
authors: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Juan
authors: J
authors: Su
authors: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Rui
authors: R
authors: Fang
authors: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Mengmeng
authors: M
authors: Jin
authors: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: leizh@njau.edu.cn.
authors: Zhihai
authors: Z
authors: Lei
authors: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Yuanlong
authors: Y
authors: Hou
authors: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Zhiyu
authors: Z
authors: Ma
authors: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Tingting
authors: T
authors: Guo
mesh_terms: D015096:3-Hydroxysteroid Dehydrogenases / Q000235:genetics / Q000378:metabolism; D000818:Animals; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D007028:Hypothalamic Hormones / Q000235:genetics / Q000378:metabolism*; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology*; D007985:Leydig Cells / Q000378:metabolism; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018013:Receptors, Neuropeptide / Q000235:genetics / Q000378:metabolism; D012741:Sexual Maturation; D013254:Steroid 17-alpha-Hydroxylase / Q000235:genetics / Q000378:metabolism; D013552:Swine / Q000502:physiology*; D013737:Testis / Q000502:physiology*; D013739:Testosterone / Q000378:metabolism
chemical_list: D007028:Hypothalamic Hormones; D012333:RNA, Messenger; D018013:Receptors, Neuropeptide; C083929:neuropeptide FF receptor; D013739:Testosterone; D015096:3-Hydroxysteroid Dehydrogenases; D013254:Steroid 17-alpha-Hydroxylase
keywords: G protein-coupled receptor 147 (GPR147); G protein-coupled receptor 74 (GPR147); Gonadotropin-inhibitory hormone (GnIH); Hypothalamic–pituitary–testicular axis; Leydig cells; RFRP-3