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PubMed · 6259186

Transmembrane potential changes associated with superoxide release from human granulocytes.

G S Jones·K VanDyke·V Castranova
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Abstract

Treatment of human granulocytes with concanavalin A, phorbol myristate acetate (PMA), N-formyl-methionyl-leucyl-phenylalanine (FMLP), and A23187 (a calcium ionophore) stimulates the release of superoxide anion and the generation of chemiluminescence. The fluorescent probe, Di-S-C3(5), has been used to monitor shifts in membrane potential in response to these stimulants which precede the secretion of superoxide. Concanavalin A, PMA, and FMLP induce a biphasic shift in transmembrane potential (Em), i.e., a rapid depolarization followed by a prolonged hyperpolarization. This depolarization is dependent on both external sodium and calcium while the hyperpolarization is inhibited by ouabain which blocks the electrogenic Na-K pump. In contrast, A23187 induces a rapid and prolonged depolarization. This monophasic shift in Em is dependent on external calcium. These results suggest that depolarization acts as a signal to initiate events associated with the "respiratory burst" of these phagocytes.

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CalcimycinCalciumConcanavalin AGranulocytesHumansMembrane PotentialsN-FormylmethionineN-Formylmethionine Leucyl-PhenylalanineOligopeptidesOxygenPotassiumSodiumSuperoxidesTetradecanoylphorbol AcetateJournal Article

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G S Jones, K VanDyke, V Castranova. 1981. Transmembrane potential changes associated with superoxide release from human granulocytes.. https://doi.org/10.1002/jcp.1041060109

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