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PubMed · 8762062

Chloride channel blockers decrease intracellular pH in cultured renal epithelial LLC-PK1 cells.

C D Brown·A J Dudley
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Abstract

The effects of chloride channel blockers upon intracellular pH (pHi) were examined in renal epithelial monolayers of LLC-PK1 cells. A significant intracellular acidification was found with addition of 100 microM 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB), niflumic acid, flufenamate and diphenylamine-2-carboxylate (DPC) but not with 4,4'-diisothiocyanatostilbene-2-2'disulphonic acid (DIDS). The effects of these agents upon pHi was dose-dependent with apparent K0.5 values of: 16.7 +/- 0.3 microM, 34.2 +/- 0.9 microM and 740 +/- 13 microM for niflumic acid, flufenamate and DPC respectively. The results indicate that at concentrations commonly used to block channel activity these chloride channel blockers have profound effects upon pHi.

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4,4'-Diisothiocyanostilbene-2,2'-Disulfonic AcidAnimalsChloride ChannelsDose-Response Relationship, DrugEpitheliumHydrogen-Ion ConcentrationLLC-PK1 CellsNiflumic AcidSwineTime FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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C D Brown, A J Dudley. 1996. Chloride channel blockers decrease intracellular pH in cultured renal epithelial LLC-PK1 cells.. https://doi.org/10.1111/j.1476-5381.1996.tb15422.x

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