Histamine interaction on surface recognition sites of H₂‐type in parietal and non‐parietal cells isolated from the guinea pig stomach

Abstract

In gastric cells isolated by pronase digestion from the guinea pig, histamine stimulated CAMP production in 3 fundic cell fractions (EC50 = 1.6-2 x 10m4 M) enriched in parietal (94%), peptic (63%) and mucous cells (87%) as well as in antral cells (EC5o = 4 x 10e4M) that are devoid of parietal cells. Histamine stimulations were completely inhibited by the H2 antagonist cimetidine (Ki = 0.27-0.57 x 1O-6 M) or by the H1 antagonist diphenhydramine, but at lOO-times lower potency (Ki = 22-45.7 x 10m6 M), indicating the presence of histamine Hz receptors in parietal and nonparietal cells of the guinea pig gastric mucosa. HistamineFundic, antral cell HZ receptor Cyclic AMP Gastric secretion

Impact of Blockade of Histamine H2Receptors on Chronic Heart Failure Revealed by Retrospective and Prospective Randomized Studies

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Beta‐adrenergic regulation of cyclic adenosine 3‘,5’ monophosphate accumulation in human gastric epithelial glands. Inhibitory effect of somatostatin

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