Histamine mediates the stimulatory action of ghrelin on acid secretion in rat stomach

• Published in: Digestive diseases and sciences Vol. 51; no. 8; pp. 1313 - 1321
• Main Authors: YAKABI, Koji, RO, Shoki, ONOUHI, Tsuneko, TANAKA, Teruyuki, OHNO, Shino, MIURA, Seiichi, JOHNO, Yukimi, TAKAYAMA, Kiyoshige
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.08.2006; Springer Nature B.V
• Subjects: Animals; Biological and medical sciences; Famotidine - pharmacology; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; Gastric Acid - secretion; Ghrelin; Growth Hormone; Histamine - metabolism; Histamine H2 Antagonists - pharmacology; Histidine Decarboxylase - genetics; Male; Peptide Hormones - pharmacology; Rats; Rats, Wistar; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - drug effects; RNA, Messenger - metabolism; Stomach - drug effects; Stomach - innervation; Stomach - metabolism; Vagotomy; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Stomach; Rat; Secretion; Rodentia; Metabolic diseases; Appetite stimulant; Isolated organ; Vagal nerve, Isolated vascularly perfused rat stomach; Histamine; Vertebrata; Mammalia; Ghrelin; Animal; Gastroenterology; Acid secretion Histamine; Vagus nerve
• ISSN: 0163-2116; 1573-2568
• DOI: 10.1007/s10620-005-9002-3

Ghrelin, a novel growth hormone-releasing peptide, is present in the rat and human stomach and is known to stimulate acid secretion and stomach motility. However, the mechanism of action of ghrelin is not fully understood. In the present study, we attempted to elucidate the role of histamine in ghrelin-induced acid secretion in rat stomach. Intravenous administration of ghrelin at 0.8 to 20 microg/kg dose dependently increased gastric acid secretion, as measured by the gastric lumen perfusion method. The maximum response was almost equal to that of gastrin (20 microg/kg). These actions were abolished by bilateral subdiaphragmatic vagotomy. Famotidine (0.33 mg/kg) also completely inhibited the effects of ghrelin. Furthermore, ghrelin increased histidine decarboxylase (HDC) messenger RNA (mRNA) levels, as measured by real-time reverse transcription-polymerase chain reaction using LightCycler. The action of ghrelin on HDC mRNA was abolished by vagotomy. Ghrelin did not affect histamine release from isolated vascularly perfused rat stomach. Taken together, these results suggest that ghrelin stimulates gastric acid secretion via a mechanism involving activation of vagal efferent nerve and histamine release from gastric enterochromaffin-like cells.