title: Synergistic action of gastrin and ghrelin on gastric acid secretion in rats.
abstract: Gastrin and ghrelin are secreted from G cells and X/A-like cells in the stomach, respectively, and respective hormones stimulate gastric acid secretion by acting through histamine and the vagus nerve. In this study, we examined the relationship between gastrin, ghrelin and gastric acid secretion in rats. Intravenous (iv) administration of 3 and 10 nmol of gastrin induced transient increases of ghrelin levels within 10 min in a dose-dependent manner. Double immunostaining for ghrelin and gastrin receptor revealed that a proportion of ghrelin cells possess gastrin receptors. Although (iv) administration of gastrin or ghrelin induced significant gastric acid secretion, simultaneous treatment with both hormones resulted in a synergistic, rather than additive, increase of gastric acid secretion. This synergistic increase was not observed in vagotomized rats. These results suggest that gastrin may directly stimulate ghrelin release from the stomach, and that both hormones may increase gastric acid secretion synergistically.
authors.affiliation: Department of Veterinary Physiology, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Fukumoto
authors.forename: Keiko
authors.initials: K
authors.lastname: Nakahara
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Katayama
authors.forename: Mikiya
authors.initials: M
authors.lastname: Miyazatao
authors.forename: Kenji
authors.initials: K
authors.lastname: Kangawa
authors.forename: Noboru
authors.initials: N
authors.lastname: Murakami
mesh_terms: D000818:Animals; D005744:Gastric Acid / Q000378:metabolism*; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism*; D005755:Gastrins / Q000008:administration & dosage / Q000502:physiology*; D054439:Ghrelin / Q000008:administration & dosage / Q000502:physiology*; D007275:Injections, Intravenous; D008297:Male; D051381:Rats; D017208:Rats, Wistar
chemical_list: D005755:Gastrins; D054439:Ghrelin