L-Ornithine stimulates growth hormone release in a manner dependent on the ghrelin system. Issue 6 (17th May 2017)

• Record Type: Journal Article
• Authors: Ho, Yee Yin; Nakato, Junya; Mizushige, Takafumi; Kanamoto, Ryuhei; Tanida, Mamoru; Akiduki, Saori; Ohinata, Kousaku
• Is Part Of: Food & function. Volume 8:Issue 6(2017)
• Page Start: 2110
• Page End: 2114
• Publication Date: 2017-05-17
• Subjects: Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; Nutrition -- Periodicals; 664.07
• DOI: 10.1039/c7fo00309a
• Languages: English
• ISSNs: 2042-6496

Abstract

Abstract : Stimulation of growth hormone release induced by intraduodenally administeredl -ornithine was mediated by the ghrelin system in rats. Abstract : We found that intraduodenal administration ofl -ornithine (l -Orn) stimulates growth hormone (GH) secretion in Wistar rats, and then investigated its mechanism. GH-releasing activity after intraduodenal administration ofl -Orn was blocked by [d -Lys 3 ]-GHRP-6, an antagonist of the ghrelin receptor; however, l -Orn (100 μM) has no affinity for the ghrelin receptor, suggesting that the GH-releasing activity ofl -Orn is mediated via ghrelin release and activation of the ghrelin receptor. Intraduodenally administeredl -Orn increased ghrelin mRNA expression in the duodenum but not in the stomach or hypothalamus. In addition, l -Orn-induced GH-releasing activity was inhibited by propranolol, an antagonist of β-adrenergic receptor, which is known to be coupled to ghrelin release. In conclusion, intraduodenally administeredl -Orn stimulates GH secretion through the sympathetic nervous and ghrelin systems.