Interaction of Helicobacter pylori and its fatty acids with parietal cells and gastric H+/K(+)-ATPase.
Helicobacter pylori and the fatty acids produced by this organism were compared for their acid inhibitory activity in isolated parietal cells and their interaction with gastric H+/K(+)-ATPase. H pylori (intact organisms, sonicates, methanolic extracts, and extracts from culture medium) and the fatty acids cis 9,10-methyleneoctadecanoic acid and tetradecanoic acid inhibited at fairly high concentrations histamine- and dibutyryl cyclic adenosine monophosphate stimulated acid production in isolated parietal cells, dissipated (with a slow onset) the H+/K(+)-ATPase created H+ gradient in gastric membrane vesicles, and inhibited H+/K(+)-ATPase activity in a concentration dependent manner. The inhibitory potency of H pylori and the fatty acids in relation to H+/K(+)-ATPase depended on the amount of membrane protein. Bovine serum albumin prevented enzyme inhibition and proton dissipation from gastric vesicles. The data indicate that H pylori establishes its antisecretory action in parietal cells by blocking H+/K(+)-ATPase activity and also by a detergent action at the apical parietal cell membrane. The fatty acids cis 9,10-methyleneoctadecanoic acid and tetradecanoic acid are probably the acid inhibitory factors secreted by H pylori.
Department of General Pharmacology, Medizinische Hochschule Hannover, Germany.
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Beil
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Birkholz
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Wagner
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D000818:Animals; D002478:Cells, Cultured; D003864:Depression, Chemical; D004794:Enzyme Repression; D005227:Fatty Acids / Q000378:metabolism* / Q000494:pharmacology; D005744:Gastric Acid / Q000378:metabolism; D005753:Gastric Mucosa / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D006168:Guinea Pigs; D017506:H(+)-K(+)-Exchanging ATPase / Q000378:metabolism*; D016480:Helicobacter pylori / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D019814:Myristic Acid; D009227:Myristic Acids / Q000494:pharmacology; D011522:Protons
D005227:Fatty Acids; D008565:Membrane Proteins; D009227:Myristic Acids; D011522:Protons; D019814:Myristic Acid; C029355:dihydrosterculic acid; D017506:H(+)-K(+)-Exchanging ATPase