New Metabolic Influencer on Oxytocin Release: The Ghrelin
Department of Physiology, Anatomy and Neuroscience, Faculty of Science and Informatics, University of Szeged, 6726 Szeged, Hungary
Department of Physiology, Anatomy and Neuroscience, Interdisciplinary Excellence Centre, University Of Szeged, Szeged, Hungary
Institute of Physical Education and Sport Sciences, Gyula Juhász Faculty of Education, University of Szeged, 6725 Szeged, Hungary
Department of Medical Chemistry, Faculty of Medicine, University of Szeged, 6720 Szeged, Hungary
First Department of Internal Medicine, Faculty of Medicine, University of Szeged, 6720 Szeged, Hungary
Department of Environmental Biology and Education, Gyula Juhász Faculty of Education, Institute of Applied Science, University of Szeged, 6725 Szeged, Hungary
Department of Psychiatry, Faculty of Medicine, University of Szeged, 6725 Szeged, Hungary
HR-Pharma Ltd., 6726 Szeged, Hungary
Author to whom correspondence should be addressed.
Renáta Szabó and Rudolf Ménesi contributed equally to this paper as first authors.
The author was deceased.
Academic Editor: Béla Juhász
Molecules 2019, 24(4), 735; https://doi.org/10.3390/molecules24040735
Received: 28 January 2019 / Revised: 11 February 2019 / Accepted: 13 February 2019 / Published: 18 February 2019
(This article belongs to the Special Issue Bioactive Compounds for Metabolic Syndrome and Type 2 Diabetes-II)
Background: The hypothalamic–pituitary axis by secreting neuropeptides plays a key role in metabolic homeostasis. In light of the metabolic regulation, oxytocin is a potential neuropeptide for therapies against obesity and related disorders. The aim of our study is to measure ghrelin-induced oxytocin secretion in rats and to detect the changes after administration of ghrelin antagonist. Methods: Ghrelin was administrated centrally (intracerebroventricular, i.c.v., 1.0, 10.0, and 100.0 pmol) or systemically (intravenous, i.v., 1.0, and 10.0 nmol). [d-Lys3]-GHRP-6 ghrelin antagonist was injected 15 min before ghrelin injection in a dose of 10.0 pmol i.c.v. and 10.0 nmol i.v. Results: Either i.c.v. or i.v. administration of ghrelin dose-dependently increased the plasma oxytocin concentration. Following pretreatment with the ghrelin antagonist [d-Lys3]-GHRP-6, the high plasma oxytocin level induced by ghrelin was significantly reduced. Conclusion: The results indicate that the release of oxytocin is influenced directly by the ghrelin system. Examination of the mechanism of ghrelin-induced oxytocin secretion is a new horizon for potential therapeutic options.