Famotidine

Gastric acid secretion was stimulated by intravenous (i.v.) bolus infusion of histamine dihydrochloride (Nakarai Chemicals Co., Ltd., Kyoto, Japan), pentagastrin (Sigma Aldrich, USA), carbachol (Tocris Bioscience, Ellisville, MO), suncus motilin (Scrum Inc., Tokyo, Japan), and human acylated ghrelin (Asubio Pharma Co., Ltd., Hyogo, Japan). Famotidine (Wako Pure Chemical Industries Ltd.), YM 022 (Sigma-Aldrich), and atropine sulfate (Mylan Pharma, Osaka, Japan) were used as H₂ receptor, CCK-B receptor, and muscarinic cholinergic receptor antagonist, respectively. Motilin, ghrelin, and pentagastrin were dissolved in 0.1% BSA in PBS (phosphate-buffered saline), while histamine, carbachol, and atropine were dissolved in 0.9% saline. Famotidine was dissolved in 0.5 N HCl, and i.v. administration was performed after dilution in 0.1% BSA in PBS. YM 022 was dissolved in dimethylsulfoxide (DMSO) and subsequent dilutions were made in saline containing DMSO. All solutions were prepared immediately before each experiment. The dosage of each agent was administered at a rate of 100 μL per 100 g BW.