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PubMed · 9929373

ClC-2 activation modulates regulatory volume decrease.

H Xiong·C Li·E Garami·Y Wang·M Ramjeesingh·K Galley·C E Bear
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Abstract

ClC-2 belongs to a large family of chloride channels and its expression in certain cell types is associated with the appearance of swelling-activated chloride (Cl-) currents. In the present report, we examined the hypothesis that ClC-2 plays a role in regulatory volume decrease by expressing ClC-2 in Sf9 cells using the baculovirus system. First, we showed that ClC-2 protein expression is associated with appearance of a Cl- conductance which is activated by hypo-osmotic shock and can be distinguished from swelling-activated chloride currents endogenous to Sf9 cells on the basis of its pharmacology and specific inhibition by an anti-ClC-2 antibody. Second, we show that the rate of regulatory volume decrease is significantly enhanced in Sf9 cells expressing ClC-2 protein. Hence, our data support the hypothesis that ClC-2 is capable of mediating regulatory volume decrease.

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4,4'-Diisothiocyanostilbene-2,2'-Disulfonic AcidAnimalsAntibodiesCLC-2 Chloride ChannelsCell LineCell SizeChloride ChannelsGene ExpressionGramicidinImmunoblottingIn Vitro TechniquesLightMeglumineNerve Tissue ProteinsNitrobenzoatesOsmotic PressurePatch-Clamp TechniquesPerfusionRatsSpodopteraTransfectionJournal ArticleResearch Support, Non-U.S. Gov't

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H Xiong, C Li, E Garami, Y Wang, M Ramjeesingh, K Galley, C E Bear. 1999-02-01. ClC-2 activation modulates regulatory volume decrease.. https://doi.org/10.1007/s002329900485

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