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PubMed · 2160542

Cytoplasmic acidification and activation of Na+/H+ exchange during regulatory volume decrease in Ehrlich ascites tumor cells.

A Livne·E K Hoffmann
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Abstract

Ehrlich ascites tumor cells undergoing regulatory volume decrease (RVD) exhibit cytoplasmic acidification as measured by an intracellular fluorescent pH indicator. The acidification results in an activation of the Na+/H+ exchanger. The intracellular pH 'set point' for the activation is estimated to be around 7.0. The activation of the Na+H+ exchanger leads to an incomplete RVD. In support of this conclusion, amiloride and Na+-free medium, known to limit the Na+/H+ exchange, indeed enhance the RVD response. Intracellular acidification and activation of Na+/H+ exchange may be a general response of cells undergoing RVD.

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AmilorideAnimalsCarcinoma, Ehrlich TumorCarrier ProteinsCytoplasmHydrogen-Ion ConcentrationIon ExchangeMiceOsmolar ConcentrationProtonsSodiumSodium-Hydrogen ExchangersTumor Cells, CulturedJournal Article

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BibTeXRIS

A Livne, E K Hoffmann. 1990. Cytoplasmic acidification and activation of Na+/H+ exchange during regulatory volume decrease in Ehrlich ascites tumor cells.. https://doi.org/10.1007/bf01869096

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