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. 1994 Feb;103(2):153-79.
doi: 10.1085/jgp.103.2.153.

Hypotonicity activates a native chloride current in Xenopus oocytes

M J Ackerman  1 , K D Wickman, D E Clapham
Affiliations

Hypotonicity activates a native chloride current in Xenopus oocytes

M J Ackerman et al. J Gen Physiol. 1994 Feb.

Abstract

Xenopus oocytes are frequently utilized for in vivo expression of cellular proteins, especially ion channel proteins. A thorough understanding of the endogenous conductances and their regulation is paramount for proper characterization of expressed channel proteins. Here we detail a novel chloride current (ICl.swell) responsive to hypotonicity in Xenopus oocytes using the two-electrode voltage clamp technique. Reducing the extracellular osmolarity by 50% elicited a calcium-independent chloride current having an anion conductivity sequence identical with swelling-induced chloride currents observed in epithelial cells. The hypotonicity-activated current was blocked by chloride channel blockers, trivalent lanthanides, and nucleotides. G-protein, cAMP-PKA, and arachidonic acid signaling cascades were not involved in ICl.swell activation. ICl.swell is distinct from both stretch-activated nonselective cation channels and the calcium-activated chloride current in oocytes and may play a critical role in volume regulation in Xenopus oocytes.

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References

    1. Pflugers Arch. 1992 Sep;421(6):530-8 - PubMed
    1. Science. 1992 Nov 27;258(5087):1477-9 - PubMed
    1. Nature. 1992 Dec 24-31;360(6406):759-62 - PubMed
    1. Pflugers Arch. 1992 Nov;422(2):143-50 - PubMed
    1. J Biol Chem. 1993 Feb 25;268(6):3821-4 - PubMed

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