title: Developmental changes in the long form leptin receptor and related neuropeptide gene expression in the pig brain.
abstract: The hypothalamus is the key site of central regulation of energy homeostasis, appetite, and reproduction. The long form leptin receptor (Ob-Rl) is localized within the hypothalamus along with several neuropeptides that are involved in regulation of the neuroendocrine axis. In the present study, developmental changes in gene expression of the Ob-Rl, preproorexin, proopiomelanocortin (POMC), corticotropin releasing factor (CRF), somatostatin, and GnRH in the hypothalamus was studied. Expression of Ob-Rl and neuropeptide mRNA was examined by semiquantitative reverse transcription-polymerase chain reaction in hypothalami collected from 106-day-old fetus (n = 3) and 7-day-old (n = 3), 3.5-mo-old (n = 3), and 6-mo-old (n = 2) gilts. In addition, leptin mRNA expression in the first three ages was examined in back fat. Leptin mRNA expression increased (P < 0.05) by 7 days postnatal, but Ob-Rl mRNA expression increased (P < 0.01) by 3.5 mo. Expression of preproorexin (P < 0.05), somatostatin, and GnRH (P < 0.01) mRNA peaked by 3.5 mo of age while POMC mRNA expression increased markedly (P < 0.01) by 6 mo of age. The CRF mRNA expression did not change across ages. These findings suggest a possible relationship among Ob-Rl and a number of hypothalamic and peripheral peptides in the development of the neuroendocrine axis. These peptides may serve as messengers that link mechanisms that regulate reproduction and energy balance.
authors.affiliation: Department of Animal and Dairy Science, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: J
authors.initials: J
authors.lastname: Lin
authors.forename: C
authors.initials: C
authors.lastname: Richard Barb
authors.forename: R R
authors.initials: RR
authors.lastname: Kraeling
authors.forename: G B
authors.initials: GB
authors.lastname: Rampacek
mesh_terms: D000818:Animals; D001921:Brain / Q000196:embryology* / Q000378:metabolism; D002352:Carrier Proteins / Q000032:analysis / Q000235:genetics*; D003346:Corticotropin-Releasing Hormone / Q000235:genetics; D005260:Female; D015870:Gene Expression; D005865:Gestational Age; D007987:Gonadotropin-Releasing Hormone / Q000235:genetics; D007031:Hypothalamus / Q000737:chemistry / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D020738:Leptin / Q000235:genetics; D009479:Neuropeptides / Q000235:genetics*; D064446:Orexin Receptors; D000068797:Orexins; D011247:Pregnancy; D011333:Pro-Opiomelanocortin / Q000235:genetics; D011498:Protein Precursors / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D054411:Receptors, Leptin; D018013:Receptors, Neuropeptide; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013004:Somatostatin / Q000235:genetics; D013552:Swine / Q000196:embryology*
chemical_list: D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D020738:Leptin; D009479:Neuropeptides; D064446:Orexin Receptors; D000068797:Orexins; D011498:Protein Precursors; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D054411:Receptors, Leptin; D018013:Receptors, Neuropeptide; D007987:Gonadotropin-Releasing Hormone; D013004:Somatostatin; D011333:Pro-Opiomelanocortin; D003346:Corticotropin-Releasing Hormone