{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T21:20:59Z","timestamp":1790630459687,"version":"4.1.0"},"reference-count":48,"publisher":"The Endocrine Society","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2010,5,1]]},"abstract":"<jats:p>With the exception of modern mammals, most vertebrate species possess two GnRH genes, GnRH-1 and GnRH-2. In addition, in many teleost fish, there is a third gene called GnRH-3. If the main function of GnRH-1 is unambiguously to stimulate gonadotropin release, the other two GnRH forms still lack clear functions. This is particularly true for the highly conserved GnRH-2 that encodes chicken GnRH-II. This GnRH variant is consistently expressed in neurons of the dorsal synencephalon in most vertebrate groups but still has no clear functions supported by anatomical, pharmacological, and physiological data. In this study performed on a perciform fish, the European sea bass, we show for the first time that the pineal organ receives GnRH-2-immunoreactive fibers originating from the synencephalic GnRH-2 neurons. This was shown through a combination of retrograde tracing and immunohistochemistry, using highly specific antibodies. Supporting the presence of GnRH-2 functional targets, RT-PCR data together with the in situ hybridization studies showed that the sea bass pineal gland strongly expressed a GnRH receptor (dlGnRHR-II-2b) with clear selectivity for GnRH-2 and, to a lesser extent, the dlGnRHR-II-1a subtype. Finally, in vitro and in vivo experiments demonstrate stimulatory effects of GnRH-2 on nocturnal melatonin secretion by the sea bass pineal organ. Altogether, these data provide, for the first time in a vertebrate species, converging evidence supporting a role of GnRH-2 in the modulation of fish pineal functions.<\/jats:p>","DOI":"10.1210\/en.2009-1207","type":"journal-article","created":{"date-parts":[[2010,3,9]],"date-time":"2010-03-09T22:23:52Z","timestamp":1268173432000},"page":"2265-2275","source":"Crossref","is-referenced-by-count":82,"title":["The Highly Conserved Gonadotropin-Releasing Hormone-2 Form Acts as a Melatonin-Releasing Factor in the Pineal of a Teleost Fish, the European Sea Bass Dicentrarchus labrax"],"prefix":"10.1210","volume":"151","author":[{"given":"Arianna","family":"Servili","sequence":"first","affiliation":[{"name":"Departamento de Biologi\u0301a (A.S., J.A.M.-C.), Facultad de Ciencias del Mar y Ambientales, Universidad de Ca\u0301diz, E-11510 Puerto Real, Spain"},{"name":"Neurogenesis and Estrogens (A.S., C.L., O.K.), Unite\u0301 Mixte de Recherche Centre National de la Recherche Scientifique 6026, Institut Fe\u0301de\u0301ratif de Recherche (IFR) 140"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christe\u0300le","family":"Lethimonier","sequence":"first","affiliation":[{"name":"Neurogenesis and Estrogens (A.S., C.L., O.K.), Unite\u0301 Mixte de Recherche Centre National de la Recherche Scientifique 6026, Institut Fe\u0301de\u0301ratif de Recherche (IFR) 140"},{"name":"Institut National de la Sante\u0301 et de la Recherche Me\u0301dicale U625, Groupe d\u2019Etude de la Reproduction chez l\u2019Homme et les Mammife\u0300res (GERHM) (C.L.), IFR140, Universite\u0301 de Rennes 1, Campus de Beaulieu, 35042 Rennes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean-Jacques","family":"Lareyre","sequence":"first","affiliation":[{"name":"Sexualite\u0301 et Reproduction des Poissons (J.-J.L.), Institut National de la Recherche Agronomique, Station Commune de Recherches en Ichtyophysiologie, Biodiversite\u0301 et Environnement (SCRIBE), IFR140, Universite\u0301 de Rennes 1, Campus de Beaulieu, 35042 Rennes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jose\u0301 Fernando","family":"Lo\u0301pez-Olmeda","sequence":"first","affiliation":[{"name":"Departamento de Biologi\u0301a (A.S., J.A.M.-C.), Facultad de Ciencias del Mar y Ambientales, Universidad de Ca\u0301diz, E-11510 Puerto Real, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francisco Javier","family":"Sa\u0301nchez-Va\u0301zquez","sequence":"first","affiliation":[{"name":"Departamento de Fisiologi\u0301a (J.F.L.-O., F.J.S.-V.), Facultad de Biologi\u0301a, Universidad de Murcia, Campus de Espinardo, E-30100 Murcia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olivier","family":"Kah","sequence":"first","affiliation":[{"name":"Neurogenesis and Estrogens (A.S., C.L., O.K.), Unite\u0301 Mixte de Recherche Centre National de la Recherche Scientifique 6026, Institut Fe\u0301de\u0301ratif de Recherche 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