title: Direct evidence for the co-expression of URP and GnRH in a sub-population of rat hypothalamic neurones: anatomical and functional correlation.
abstract: Urotensin-II-related peptide (URP) is an eight amino-acid neuropeptide recently isolated from rat brain and considered as the endogenous ligand for the GPR14 receptor. Using single and double immunohistochemical labelling, in situ hybridization and ultrastructural immunocytochemistry, we explored the cellular and subcellular localization of URP in the male rat brain. URP peptide was detected in numerous varicose fibres of the median eminence (ME) and organum vasculosum laminae terminalis (OVLT) as well as in neuronal cell bodies of the medial septal nucleus and diagonal band of Broca where corresponding mRNA were also detected. Combining in situ hybridization with immunohistochemistry, we showed that cell bodies of the rat anterior hypothalamus contained both URP mRNA and GnRH peptide. In addition, double ultrastructural immunodetection of URP and GnRH peptides clearly revealed, in the median eminence, the co-localization of both peptides in the same neuronal processes in the vicinity of fenestrated portal vessels. This remarkable cellular and subcellular distribution led us to test the effect of URP on the GnRH-induced gonadotrophins release in the anterior pituitary, and to discuss its putative role at the level of the median eminence.
authors: Laboratoire de Neurobiologie des Signaux Intercellulaires, CNRS UMR 7101-Université Pierre et Marie Curie, Paris, France.
authors: Johann-Günther
authors: JG
authors: Egginger
authors: Caroline
authors: C
authors: Parmentier
authors: Ghislaine
authors: G
authors: Garrel
authors: Joëlle
authors: J
authors: Cohen-Tannoudji
authors: Alain
authors: A
authors: Camus
authors: André
authors: A
authors: Calas
authors: Hélène
authors: H
authors: Hardin-Pouzet
authors: Valérie
authors: V
authors: Grange-Messent
mesh_terms: D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D017931:DNA Primers; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism*; D007031:Hypothalamus / Q000166:cytology / Q000378:metabolism*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D008854:Microscopy, Electron; D009474:Neurons / Q000378:metabolism*; D036361:Peptide Hormones / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D017931:DNA Primers; D036361:Peptide Hormones; C479081:urotensin II-related peptide, rat; D007987:Gonadotropin-Releasing Hormone