title: Different signaling in pig anterior pituitary cells by GnRH and its complexes with copper and nickel.
abstract: Gonadotropin releasing hormone (GnRH) is an essential factor in the regulation of synthesis and release of pituitary gonadotropins. After binding to specific receptors and coupling with G proteins, it triggers the intracellular signaling involving the synthesis of inositol phosphates and diacylglycerol. Previously we have showed that certain metal complexes with GnRH, i.e. copper (Cu-GnRH) and nickel (Ni-GnRH) are able to bind to the GnRH receptors. The intracellular signalling of these complexes, however, has not been yet elucidated. In this experiment, the ability of the Cu-GnRH and Ni-GnRH complexes to modulate cAMP synthesis and phosphoinositols formation in the pig anterior pituitary cells in vitro was studied. The native GnRH and its metal complexes stimulated the luteinizing hormone (LH) release, but only the effect of Cu-GnRH was found to be a dose-dependent. The metal complexes did not significantly influence inositol phosphates accumulation, while their effect on cAMP synthesis was significantly more potent than that of GnRH alone. We conclude that the Cu-GnRH and Ni-GnRH complexes increase LH release in the porcine pituitary cells although their intracellular signaling is different from that of the native GnRH. It seems that metal complexes with GnRH deserve more attention in further studies.
authors.affiliation: The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Jabłonna, Poland. k.kochman@ifzz.pan.pl
authors.forename: Kazimierz
authors.initials: K
authors.lastname: Kochman
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Blitek
authors.forename: Monika
authors.initials: M
authors.lastname: Kaczmarek
authors.forename: Alina
authors.initials: A
authors.lastname: Gajewska
authors.forename: Gabriela
authors.initials: G
authors.lastname: Siawrys
authors.forename: Raymond
authors.initials: R
authors.lastname: Counis
authors.forename: Adam J
authors.initials: AJ
authors.lastname: Ziecik
mesh_terms: D000818:Animals; D003300:Copper / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism*; D006868:Hydrolysis; D007295:Inositol Phosphates / Q000378:metabolism; D007986:Luteinizing Hormone / Q000378:metabolism; D009532:Nickel / Q000378:metabolism*; D010716:Phosphatidylinositols / Q000378:metabolism; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D034421:Sus scrofa
chemical_list: D007295:Inositol Phosphates; D010716:Phosphatidylinositols; D007987:Gonadotropin-Releasing Hormone; D003300:Copper; D009532:Nickel; D007986:Luteinizing Hormone; D000242:Cyclic AMP