A histamine H2 receptor antagonist, roxatidine, stimulates mucus secretion and synthesis by cultured rabbit gastric mucosal cells.
We examined the effects of the known antisecretory and mucosal protective drug, roxatidine, on the secretion and synthesis of mucus by cultured rabbit gastric mucosal cells. The amounts of secreted and synthesized mucus were determined by the [3H] glucosamine labelling method. Exposure of the cells to roxatidine for 8 hr caused increases in the secretion and synthesis of mucus in a dose-related manner. The increase in mucus synthesis was maximally induced 4 hr after the addition of roxatidine, while mucus secretion was maximally enhanced a further 4 hr later. However, other H2 antagonists such as cimetidine, rantidine and famotidine failed to stimulate the secretion and synthesis of gastric mucus. In addition, neither indomethacin nor NG-nitro-L-arginine methyl ester affected the roxatidine-induced increases in mucus secretion and synthesis. We conclude that roxatidine directly acts on gastric mucosal cells, inducing increases in both the secretion and synthesis of mucus, and that an unknown regulatory pathway might be involved in these stimulatory actions of roxatidine.
Takahashi
S
S
Department of Applied Pharmacology, Kyoto Pharmaceutical University, Japan.
Okabe
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S
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D002478:Cells, Cultured; D015232:Dinoprostone / Q000096:biosynthesis; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005753:Gastric Mucosa / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D006635:Histamine H2 Antagonists / Q000494:pharmacology*; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D009093:Mucus / Q000378:metabolism*; D019331:NG-Nitroarginine Methyl Ester; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D010880:Piperidines / Q000494:pharmacology*; D011817:Rabbits
D000894:Anti-Inflammatory Agents, Non-Steroidal; D004791:Enzyme Inhibitors; D006635:Histamine H2 Antagonists; D010880:Piperidines; D001120:Arginine; D019001:Nitric Oxide Synthase; D015232:Dinoprostone; D019331:NG-Nitroarginine Methyl Ester; D007213:Indomethacin; C053742:roxatidine acetate