Leptin receptor and neuropeptide Y gene expression in the sheep brain

Lynda Williams, Clare Lesley Adam, Julian Mercer, Kim-Marie Moar, D Slater, L Hunter, P.A. Findlay, Nigel Hoggard

Research output: Contribution to journalArticle

67 Citations (Scopus)

Abstract

Leptin, a protein secretory product of adipocytes, is important in appetite control, energy balance and reproduction, In rodents, the physiological effects of leptin are centrally mediated, in part via the neuropeptide Y (NPY) system in the hypothalamus, The role of leptin in ruminants, where appropriate nutrition and reproductive status are of major economic concern, is largely unknown. To elucidate the function of leptin in sheep we have investigated putative sites of action for leptin in the brain and pituitary gland using both in-situ hybridization to detect expression of the signalling form of the leptin receptor (OB-Rb) and in-vitro autoradiography using (I-125)leptin to detect sites of specific leptin binding, OB-Rb gene expression occurred in the hippocampus, cerebral cortex, preoptic area, stria terminalis and choroid plexus, and within the hypothalamus in the paraventricular (PVN), ventromedial (VHM) and arcuate (ARC) nuclei, OB-Rb gene expression in the ovine pituitary gland was not detected by in-situ hybridization. Sites of OB-Rb and NPY gene expression were compared using both in-situ hybridization on adjacent sections containing the arcuate and ventromedial nuclei, and dual in-situ hybridization on sections containing these areas. In serial sections, OB-Rb expression was found to correspond closely with that of NPY over the arcuate nuclei, Using dual in-situ hybridization, NPY expressing neurones in the arcuate nuclei were also positive for OB-Rb gene expression, Therefore, it appears that leptin may partly act via OB-Rb located on NPY neurones in the sheep hypothalamus as in the rodent.

Original languageEnglish
Pages (from-to)165-169
Number of pages5
JournalJournal of Neuroendocrinology
Volume11
Issue number3
DOIs
Publication statusPublished - Mar 1999

Keywords

  • leptin receptor
  • NPY
  • brain
  • pituitary
  • sheep
  • MESSENGER-RNA
  • MOUSE HYPOTHALAMUS
  • OB PROTEIN
  • DB/DB MICE
  • LOCALIZATION
  • IDENTIFICATION
  • REGIONS
  • BINDING
  • OB/OB
  • leptin receptor
  • sheep
  • messenger-RNA
  • mouse hypothalamus
  • OB protein
  • DB/DB mice
  • localization
  • identification
  • regions
  • binding

Cite this