Ghrelin Modulates Gastric Distension

In anesthetized rats, a first set of graded GD was performed. Fifteen minutes later, atropine (1 mg/kg) was injected intravenously (i.v.) to prevent acylated ghrelin stimulation of gastric motility that would have jeopardized isobaric distension of the stomach. Five minutes after atropine injection, acylated ghrelin (30 µg/kg; Phoenix Pharmaceuticals, Burlingame, CA) or saline was injected i.v. (n = 10/group). A second series of GD was started 5 min later. In one experiment, [D-Lys³]-GHRP-6 (Phoenix Pharmaceuticals, Burlingame, CA), a Ghrelin receptor antagonist, was injected (0.3 mg/kg i.v.) 10 min before acylated ghrelin injection (n = 8). The dose of peptides were selected accordingly to our previous report as the maximal effective dose to accelerate gastric emptying^{3 (link)} (Fig. 6).