Aminopyrine uptake by guinea pig gastric mucosal cells. Mediation by cyclic AMP and interactions among secretagogues
| Autor: | Jean Dyer, Shmuel Batzri |
|---|---|
| Rok vydání: | 1981 |
| Předmět: |
Male
medicine.medical_specialty Carbachol Guinea Pigs Biophysics Biochemistry Guinea pig chemistry.chemical_compound Internal medicine Gastrins medicine Gastric mucosa Cyclic AMP Animals Cimetidine Prostaglandin E1 Aminopyrine Molecular Biology HEPES Dose-Response Relationship Drug Prostaglandins E Drug Synergism Endocrinology medicine.anatomical_structure chemistry Gastric Mucosa Secretagogue Nucleotides Cyclic Histamine medicine.drug |
| Zdroj: | Biochimica et biophysica acta. 675(3-4) |
| ISSN: | 0006-3002 |
| Popis: | The role of cyclic nucleotides in regulating acid secretion by dispersed mucosal cells from guinea-pig stomach was examined by measuring first the ability of histamine and carbachol to stimulate [dimethylamine-14C]aminopyramine uptake and cyclic nucleotide metabolism and secondly, the effect of exogenous cyclic nucleotides on basal and stimulated [14C]aminopyrine uptake. The [14C]aminopyrine was found in an acidic, osmotically sensitive compartment, probably associated with the initial steps in acid secretion by these cells. Although histamine increased [14C]aminopyrine uptake and cyclic AMP synthesis as expected, histamine was approx. 10-fold more potent in inducing [14C]aminopyrine uptake. This dissociation of [14C]aminopyrine uptake and cyclic AMP metabolism process was further manifested by the observation that prostaglandin E1 failed to increase [14C]aminopyrine uptake, although it did cause a rise in cellular cyclic AMP. Furthermore, prostaglandin E1 did not alter the [14C]aminopyrine uptake caused by histamine. Carbachol was found to increase the [14C]aminopyrine uptake and also to potentiate the ability of histamine to increase [14C]aminopyrine uptake. Carbachol, however, affected neither the histamine-induced increase in cyclic AMP nor the binding of [3H]histamine to the cells. Cimetidine, a histamine H2 receptor antagonist, blocked the [14C]aminopyrine uptake induced either by histamine alone or by the potentiating combination of histamine plus carbachol. These results suggest that cyclic AMP is mediating the action of histamine on [14C]aminopyrine uptake but changes in cyclic AMP per se are not necessarily the cause for the potentiated increase in [14C]aminopyrine uptake. Furthermore, the potentiated response observed with histamine plus carbachol on [14C]aminopyrine uptake occurs at a biochemical step distal to and not obviously related to cyclic AMP generation. |
| Databáze: | OpenAIRE |
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