Effect and mechanism of ghrelin and its synthetic peptide growth hormone releasing peptide 6 on gastric motor in mice.
- Author:
Wen-Cai QIU
1
;
Zhi-Gang WANG
;
Wei-Gang WANG
;
Qi ZHENG
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Female; Gastric Emptying; drug effects; Ghrelin; pharmacology; Male; Mice; Mice, Inbred C57BL; Oligopeptides; pharmacology; Stomach; drug effects; physiology
- From: Chinese Journal of Gastrointestinal Surgery 2008;11(2):172-176
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate the effect and mechanism of ghrelin and its synthetic peptide GHRP-6 on gastric motor in mice.
METHODSIn vivo, the dose-dependent effects of ghrelin (20,50,100,200 mug/kg) and GHRP-6 (20,50,100,200 mug/kg) on gastric emptying were measured by intragastric application of phenol red test which was adapted for use in mice. The effects of atropine, NG-nitro-L-arginine methyl ester (L-NAME), and D-Lys(3)-GHRP-6 (GHS-R antagonist) on the gastric motor induced by ghrelin and GHRP-6 (100 mug/kg) were also investigated. In vitro, the effects of ghrelin (0.01,0.1,1.0,10.0 mumol/L) and GHRP-6 (0.01,0.1,1.0,10.0 mumol/L) on spontaneous contraction of mice fundic muscle strips were studied as well.
RESULTSBoth ghrelin (50,100,200 mug/kg) and GHRP-6 (50,100,200 mug/kg) significantly accelerated gastric emptying (P<0.05), but they failed to accelerate gastric emptying in the presence of atropine, L-NAME and D-Lys(3)-GHRP-6 (P<0.05). Ghrelin (0.1, 1.0, 10.0 mumol/L) and GHRP-6 (0.1, 1.0, 10.0 mumol/L) induced significant contraction of fundic muscle strips in concentration-dependent manner (P<0.05), which could be blocked by tetrodotoxin.
CONCLUSIONGhrelin and its synthetic peptide GHRP-6 accelerate gastric emptying perhaps by activating GHS-R of cholinergic excitatory pathways and nitrergic nervous pathways in the enteric nervous system.
