Involvement of orexigenic peptides in the mechanism of gastric mucosal integrity and healing of chronic gastric ulcers.
Orexigenic peptides are group of endocrine hormones exerting a pleiotropic influence on many physiological functions including regulation of the feeding behaviour and energy expenditure, release of growth hormone (GH) and inotropic effects on the heart. Some of these peptides such as ghrelin, originally identified in the gastric mucosa, has been involved not only in control of food intake and growth hormone release but also exerts the immunomodulatory and anti-inflammatory properties. This review summarizes the recent attempts to prove the concept that orexigenic peptides such as ghrelin, orexin-A and obestatin besides playing an important role in the mechanism of food intake, exhibit a potent gastroprotective action against the formation of acute gastric mucosal injury induced by various ulcerogens. This protective effect depends upon vagal activity and hyperemia mediated by NOS/NO and COX/PG systems and CGRP released from sensory afferent nerves. In addition, the appetite peptides such as ghrelin and orexin-A are implicated in the mechanism of the healing of preexisting gastric ulcers due to an activation of specific GHS-R1a and OX-R1 receptors and PG/COX system.
Szlachcic
Aleksandra
A
Department of Physiology, Jagiellonian University Medical College, 16 Grzegorzecka, Street, 31-531 Cracow, Poland.
Brzozowski
Thomas
T
Majka
Jolanta
J
Pajdo
Robert
R
Konturek
Peter C
PC
Pawlik
Michal
M
Kwiecien
Slawomir
S
Drozdowicz
Danuta
D
Bielanski
Wladyslaw
W
Konturek
Stanislaw J
SJ
Pawlik
Wieslaw W
WW
D000818:Animals; D019167:Appetite Stimulants / Q000494:pharmacology*; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology; D005753:Gastric Mucosa / Q000098:blood supply / Q000187:drug effects* / Q000294:innervation; D054439:Ghrelin / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D016481:Helicobacter Infections / Q000473:pathology; D016480:Helicobacter pylori; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D009479:Neuropeptides / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D018377:Neurotransmitter Agents / Q000494:pharmacology; D000068797:Orexins; D051381:Rats; D013276:Stomach Ulcer / Q000188:drug therapy* / Q000473:pathology
D019167:Appetite Stimulants; D052246:Cyclooxygenase 2 Inhibitors; D054439:Ghrelin; C000596229:HCRT protein, human; D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D000068797:Orexins