In vitro effect of leptin on somatolactin release in the European sea bass (Dicentrarchus labrax): dependence on the reproductive status and interaction with NPY and GnRH.
The aim of the present work was to investigate the neuroendocrine control of pituitary somatolactin (SL) release using dispersed pituitary cell culture obtained from male European sea bass (Dicentrarchus labrax) at different stages of sexual development. The effect of mouse recombinant leptin, sea bream gonadotropin releasing-hormone (sbGnRH) and porcine neuropeptide Y (pNPY) and their potential interaction on the SL release were investigated. High doses of leptin (10(-8)-10(-6)M) were differentially effective in inducing SL release depending on the sexual developmental stage. Porcine NPY alone was not effective on basal SL release, but it dose-dependently (0.1 and 1 nM) enhanced SL release induced by leptin (10(-6) and 10(-8)M) in late pre-pubertal but not in post-pubertal stages. No effect of sbGnRH in association or not with leptin was observed on SL release. These findings are the first evidences that leptin and pNPY can play an important role in the neuroendocrine control of pars intermedia function and SL release in fish. In addition, the sensitivity of SL producing cells to leptin and NPY only in prepubertal and pubertal stages, provides the potential role of SL in the nutritional control of the onset of puberty.
Peyon
Pierre
P
Instituto de Acuicultura de Torre de la Sal, Consejo Superior de Investigaciones Cientificas, 12595 Ribera de Cabanes, Castellón, Spain.
Vega-Rubín de Celis
Silvia
S
Gómez-Requeni
Pedro
P
Zanuy
Silvia
S
Pérez-Sánchez
Jaume
J
Carrillo
Manuel
M
D000818:Animals; D019167:Appetite Stimulants / Q000494:pharmacology*; D001492:Bass / Q000378:metabolism*; D002478:Cells, Cultured; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000096:biosynthesis / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D029941:Fish Proteins; D006023:Glycoproteins / Q000378:metabolism*; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D020738:Leptin / Q000494:pharmacology*; D008297:Male; D051379:Mice; D009478:Neuropeptide Y / Q000494:pharmacology*; D010902:Pituitary Gland / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D010907:Pituitary Hormones / Q000378:metabolism*; D011994:Recombinant Proteins / Q000494:pharmacology; D012098:Reproduction / Q000187:drug effects*; D012741:Sexual Maturation; D013552:Swine
D019167:Appetite Stimulants; D018076:DNA, Complementary; D029941:Fish Proteins; D006023:Glycoproteins; D020738:Leptin; D009478:Neuropeptide Y; D010907:Pituitary Hormones; D011994:Recombinant Proteins; C064448:somatolactin protein, fish; D007987:Gonadotropin-Releasing Hormone