Event Abstract Back to Event DIFFERENTIAL INVOLVEMENT OF PKC AND PKA IN GHRELIN-INDUCED GROWTH HORMONE AND GONADOTROPIN RELEASE FROM PRIMARY CULTURES OF DISPERSED GOLDFISH PITUITARY CELLS. Caleb L. Grey1 and John P. Chang1* 1 University of Alberta, Biological Sciences, Canada Ghrelin (GRLN) stimulates feeding and the release of pituitary growth hormone (GH) and maturational gonadotropin (LH) in goldfish, thus providing a possible link between energy balance and reproduction. Previous work shows that mRNAs for GRLN and its receptors are expressed in the goldfish pituitary. Extracellular Ca2+ entry through L-type voltage-sensitive Ca2+ channels and increases in intracellular Ca2+ are important signaling components leading to goldfish (g)GRLN19-elicited GH and LH release. In this study, we examined the role of protein kinase C (PKC) and A (PKA) in gGRLN19-induced hormone secretion via column perifusion of dispersed goldfish pituitary cells, and single cell Ca2+-imaging of identified goldfish somatotropes and gonadotropes. PKC inhibitors (bisindolylmaleimide-II and Gö 6976) attenuated gGRLN19-stimulated hormone secretion and associated Ca2+ signals. gGRLN19-induced hormone release and Ca2+ signals were not observed when cells were already stimulated by a PKC agonist (DiC8). PKA inhibitors (H-89 and KT5720), however, only inhibited gGRLN19-induced hormone release and Ca2+ responses in LH cells. On the other hand, an adenylate cyclase activator (forskolin) enhanced gGRLN19-induced GH, but not LH, release. Ca2+ signals elicited by combined forskolin and gGRLN19 treatment were not different from those to either treatment alone in either cell type. These results suggest that while PKC and PKA mediate GRLN actions on LH release by actions upstream of Ca2+ signals, similar responses in GH cells only involve PKC. In addition, activation of PKA may enhance GRLN-stimulated GH secretion by actions downstream of Ca2+ changes. (Supported by NSERC.) Acknowledgements NSERC University of Alberta, Biological Sciences Province of Alberta Keywords: calcium imaging, Goldfish ghrelin, Goldfish pituitary, identified gonadotropes, identified somatotropes, perifusion, PKA, PKC Conference: NASCE 2011: The inaugural meeting of the North American Society for Comparative Endocrinology, Ann Arbor, United States, 13 Jul - 16 Jul, 2011. Presentation Type: Oral Presentation Topic: Neuroendocrine control of reproduction Citation: Grey CL and Chang JP (2011). DIFFERENTIAL INVOLVEMENT OF PKC AND PKA IN GHRELIN-INDUCED GROWTH HORMONE AND GONADOTROPIN RELEASE FROM PRIMARY CULTURES OF DISPERSED GOLDFISH PITUITARY CELLS.. Front. Endocrinol. Conference Abstract: NASCE 2011: The inaugural meeting of the North American Society for Comparative Endocrinology. doi: 10.3389/conf.fendo.2011.04.00135 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 22 Jul 2011; Published Online: 09 Aug 2011. * Correspondence: Dr. John P Chang, University of Alberta, Biological Sciences, Edmonton, Canada, john.chang@ualberta.ca Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Caleb L Grey John P Chang Google Caleb L Grey John P Chang Google Scholar Caleb L Grey John P Chang PubMed Caleb L Grey John P Chang Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.