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PubMed · 8390836

Cyclic AMP-phosphodiesterase IIIA1 inhibitors decrease cytosolic Ca2+ concentration and increase the Ca2+ content of intracellular storage sites in human platelets.

P Roevens·D de Chaffoy de Courcelles
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Abstract

The effect of cyclic AMP-phosphodiesterase (cAMP-PDE) inhibitors on Ca2+ homeostasis in human platelets was studied using both quin-2 (2-(bis-(acetylamino)-5-methyl-phenoxy)methyl-6-methoxy-8-bis-(acetylami no) quinoline) and chlorotetracycline (CTC) to measure changes in cytosolic Ca2+ as well as changes in the amount of Ca2+ accumulated in intracellular storage sites. At therapeutic concentrations (1 microM) milrinone and R 80 122 but not enoximone decreased the cytosolic Ca2+ concentration in the resting platelet while the Ca2+ content in intracellular stores was increased. These observations are in accord with the proposed mechanism of action of cAMP-PDE inhibitors on cardiomyocites and highlight the particular role of cAMP in regulation of Ca2+ homeostasis.

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3',5'-Cyclic-AMP PhosphodiesterasesAminoquinolinesBlood PlateletsCalciumChlortetracyclineCytosolEnoximoneHeartHomeostasisHumansImidazolesMilrinonePhosphodiesterase InhibitorsPyridonesQuinazolinesComparative StudyJournal Article

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P Roevens, D de Chaffoy de Courcelles. 1993-06-09. Cyclic AMP-phosphodiesterase IIIA1 inhibitors decrease cytosolic Ca2+ concentration and increase the Ca2+ content of intracellular storage sites in human platelets.. https://doi.org/10.1016/0006-2952(93)90199-7

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