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Ca2(+)-driven [3H]arachidonate release in electropermeabilized human platelets shows an absolute requirement for MgATP2-.

S Patel·M C Scrutton
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Abstract

Addition of micromolar Ca2+ to electropermeabilized human platelets which had been pre-labelled with [3H]arachidonate causes release of 3H only when millimolar concentrations of a nucleoside triphosphate, e.g. ATP, are present in the incubation medium. Addition of millimolar Ca2+ in the absence of ATP, or preincubation with ATP before addition of micromolar Ca2+, fails to cause a significant increase in 3H release. Purine nucleotides are more effective than pyrimidine nucleotides in activating Ca2(+)-driven 3H release. This activation does not appear to involve phosphate transfer, since metabolically stable analogues of ATP, e.g. the beta gamma-imido analogue, are effective in promoting 3H release.

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Adenosine TriphosphateArachidonic AcidArachidonic AcidsBlood PlateletsCalciumCell Membrane PermeabilityElectric StimulationHumansIn Vitro TechniquesKineticsPhospholipidsRibonucleotidesTritiumJournal ArticleResearch Support, Non-U.S. Gov't

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S Patel, M C Scrutton. 1991-02-01. Ca2(+)-driven [3H]arachidonate release in electropermeabilized human platelets shows an absolute requirement for MgATP2-.. https://doi.org/10.1042/bj2730561

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