title: Does ghrelin explain accelerated gastric emptying in the early stages of diabetes mellitus?
abstract: During the early stages of diabetes, gastric emptying is often accelerated, rather than delayed. The mechanism of accelerated gastric emptying in diabetes has not been fully studied. A recent study showed that plasma ghrelin levels were elevated in diabetes. As postprandial antropyloric coordination plays an important role in mediating solid gastric emptying, we hypothesize that the elevated plasma ghrelin levels increase postprandial antropyloric coordination to accelerate emptying in the early stages of diabetes. To test this hypothesis, rats were made diabetic by streptozotocin (STZ; 50 mg/kg) injection, and, 2 wk later, pre- and postprandial plasma ghrelin levels, antropyloric coordination, and solid gastric emptying were determined. In control rats, plasma ghrelin levels were immediately reduced after feeding. In contrast, plasma ghrelin levels remained within the fasted levels in STZ rats after feeding. In STZ rats, gastric emptying was significantly accelerated (77.4 +/- 3.2%, n = 6), compared with that of control rats (58.8 +/- 2.5%, n = 6, P < 0.05). Treatments with anti-ghrelin antibodies attenuated accelerated gastric emptying in STZ rats (50.1 +/- 3.5%, n = 6, P < 0.05), while having little effect in vehicle control rats. The incidence of postprandial antropyloric coordination was significantly increased in STZ rats, compared with that of control rats (P < 0.05). Treatments with anti-ghrelin antibodies suppressed this enhanced antropyloric coordination in STZ rats. Our study suggests that elevated endogenous ghrelin enhances antropyloric coordination, which accelerates gastric emptying in the early stages of diabetes.
authors.affiliation: Department of Surgery, Duke University Medical Center and Durham Veterans Affairs Medical Center, Durham, NC, USA.
authors.forename: Hajime
authors.initials: H
authors.lastname: Ariga
authors.forename: Kenji
authors.initials: K
authors.lastname: Imai
authors.forename: Cindy
authors.initials: C
authors.lastname: Chen
authors.forename: Christopher
authors.initials: C
authors.lastname: Mantyh
authors.forename: Theodore N
authors.initials: TN
authors.lastname: Pappas
authors.forename: Toku
authors.initials: T
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology / Q000494:pharmacology; D001835:Body Weight / Q000502:physiology; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D004195:Disease Models, Animal; D018450:Disease Progression; D005746:Gastric Emptying / Q000502:physiology*; D054439:Ghrelin / Q000097:blood / Q000276:immunology / Q000502:physiology*; D007328:Insulin / Q000097:blood; D008297:Male; D019518:Postprandial Period / Q000502:physiology; D011706:Pyloric Antrum / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013311:Streptozocin
chemical_list: D000888:Antibodies, Anti-Idiotypic; D054439:Ghrelin; D007328:Insulin; D013311:Streptozocin