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PubMed · 899971

A histamine-induced decrease of action potential duration in cardiac muscle mediated by the H2 receptors.

F Ledda·A Mugelli·L Mantelli
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Abstract

The effects of histamine (10(-7)--10(-5) M) on the cardiac action potential have been studied in ventricular strips of guinea pig heart, electrically driven at a constant rate. A decrease of action potential was constantly observed at histamine concentrations above 10(-6) M. No significant variations of the other electrophysiological parameters were induced by the amine. The decrease in the duration of the action potential was blocked by burimamide at a concentration (10(-4) M) which induced only a slight changes in action potential outline. It is suggested that the shortening of the repolarization phase induced by histamine is due to the H2 receptor-mediated activation of the calcium inward current, which can increase the intracellular calcium concentration influencing the potassium permeability.

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Action PotentialsAnimalsBurimamideDepression, ChemicalDrug InteractionsElectric StimulationGuinea PigsHeartHistamineIn Vitro TechniquesReceptors, HistamineReceptors, Histamine H2Time FactorsJournal Article

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BibTeXRIS

F Ledda, A Mugelli, L Mantelli. 1977. A histamine-induced decrease of action potential duration in cardiac muscle mediated by the H2 receptors.. https://doi.org/10.1007/bf01969972

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