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PubMed · 15614416

Activation of chloride current and decrease of cell volume by ATP in nasopharyngeal carcinoma cells.

Qing-Feng He·Li-Wei Wang·Jian-Wen Mao·Xue-Rong Sun·Pan Li·Ping Zhong·Si-Huai Nie·Tim Jacob·Li-Xin Chen
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Abstract

Whole-cell patch clamp and cell volume measurement techniques were used to investigate the ATP-activated chloride current and the ATP effect on cell volume in nasopharyngeal carcinoma cells. Extracellular application of ATP in micromolar concentrations activated a current with the properties of modest outward rectification and negligible time-dependent inactivation in a dose-dependent manner. The current reversed at a potential [(-0.05+/-0.03) mV] close to the Cl- equilibrium potential (-0.9 mV). Substitution of Cl- with gluconate in the extracellular solution decreased the ATP-activated current and shifted the reversal potential positively. NPPB, one of the chloride channel blockers, inhibited the current by (81.03+/-9.36)%. The current was also depressed by the P2Y purinoceptor antagonist, reactive blue 2, by (67.39+/-5.06)%. ATP (50 micromol/L) decreased the cell volume under the isotonic condition. Depletion of extracellular and intracellular Cl- abolished the ATP effect on cell volume. The results suggest that extracellular ATP of micromolar scales can induce a chloride current associated with cell volume regulation by activation of chloride channel through binding to purinoceptor P2Y.

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Adenosine TriphosphateCell SizeChloride ChannelsHumansNasopharyngeal NeoplasmsNitrobenzoatesPatch-Clamp TechniquesTumor Cells, CulturedJournal ArticleResearch Support, Non-U.S. Gov't

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Qing-Feng He, Li-Wei Wang, Jian-Wen Mao, Xue-Rong Sun, Pan Li, Ping Zhong, Si-Huai Nie, Tim Jacob, Li-Xin Chen. 2004-12-25. Activation of chloride current and decrease of cell volume by ATP in nasopharyngeal carcinoma cells.. https://pubmed.ncbi.nlm.nih.gov/15614416/

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