Extracellular ascorbate stabilization: enzymatic or chemical process?

J C Rodríguez-Aguilera; P Navas

doi:10.1007/bf00762778

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Extracellular ascorbate stabilization: enzymatic or chemical process?

J C Rodríguez-Aguilera·P Navas

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Abstract

Ascorbate is stabilized in the presence of HL-60 cells. This stabilization has been questioned as a simple chemical effect. Further properties and controls about the enzymatic nature of this stabilization are described and discussed. Our results showed that cAMP derivatives and cAMP-increasing agents stimulated the ability of HL-60 cells to stabilize ascorbate. On the other hand, tunicamycin, a glycosylation-interfering agent, inhibited this ability. These data, together with hormonal regulation, support the hypothesis of an enzymatic redox system located at the plasma membrane as being responsible for the extracellular ascorbate stabilization by HL-60 cells.

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Ascorbate Oxidase Ascorbic Acid Cell Membrane Chelating Agents Cyclic AMP Extracellular Space Free Radicals Humans Hydrogen-Ion Concentration Leukemia, Promyelocytic, Acute NADH, NADPH Oxidoreductases Neoplasm Proteins Oxidation-Reduction Temperature Tumor Cells, Cultured Journal Article Review

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J C Rodríguez-Aguilera, P Navas. 1994. Extracellular ascorbate stabilization: enzymatic or chemical process?. https://doi.org/10.1007/bf00762778

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