Control of gastric mucus phospholipid content and composition by cholinergic and adrenergic mediators.
1. The secretion of choline-containing phospholipids by gastric mucosal cells in response to neural mediators was investigated using beta-adrenergic and cholinergic agents. 2. A 2.7-fold increase in phospholipid secretion occurred with isoproterenol, while pilocarpine evoked 1.4-fold increase and the effects were inhibited by the respective antagonists. 3. The phospholipid secretory responses were stimulated by dibutyryl-cAMP and phorbol myristate acetate (PMA), but not by 4 alpha-phorbol-12,13-didecanoate which does not activate protein kinase C. The effects of dibutyryl-cAMP and PMA were additive, the the PMA induced phospholipid secretion was inhibited by a protein kinase C inhibitor, tetracaine. 4. The phospholipids secreted in response to isoproterenol showed a 2.1-fold decrease in lysophosphatidylcholine, while those secreted in response to pilocarpine were enriched 2.3-fold in lysophosphatidylcholine, and 1.5-fold in sphingomyelin, and showed 23% lower content of phosphatidylcholine. 5. The results suggest that cholinergic and beta-adrenergic mediators participate in defining the gastric mucus phospholipid content and composition, and hence influence the mucosal protective capability.
Research Center, New Jersey Dental School, University of Medicine and Dentistry of New Jersey, Newark 07103-2400.
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Slomiany
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Sengupta
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Piotrowski
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J
Piotrowski
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Slomiany
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002794:Choline / Q000378:metabolism; D005753:Gastric Mucosa / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D009093:Mucus / Q000187:drug effects / Q000378:metabolism*; D010277:Parasympathomimetics / Q000494:pharmacology*; D010703:Phorbol Esters / Q000494:pharmacology; D010743:Phospholipids / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013566:Sympathomimetics / Q000494:pharmacology*; D013748:Tetracaine / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000318:Adrenergic beta-Agonists; D010277:Parasympathomimetics; D010703:Phorbol Esters; D010743:Phospholipids; D013566:Sympathomimetics; D013748:Tetracaine; D003994:Bucladesine; D002794:Choline; D013755:Tetradecanoylphorbol Acetate