Referenced in: none

Automatically associated channels: ClC4 , ClC7

Title: Activation by acidic pH of CLC-7 expressed in oocytes from Xenopus laevis.

Authors: Linda Diewald, Johanna Rupp, Mathias Dreger, Ferdinand Hucho, Clemens Gillen, Hermann Nawrath

Journal, date & volume: Biochem. Biophys. Res. Commun., 2002 Feb 22 , 291, 421-4

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/11846422

Abstract
ClC chloride channels are important in diverse physiological functions such as transepithelial transport, cell volume regulation, excitability, and acidification of intracellular organelles. We have investigated the expression of CLC-7 in oocytes from Xenopus laevis with the two electrode voltage clamp technique and Western blot analysis. Using a specific antibody against CLC-7, we found an approximately 80 kDa protein in oocytes, previously injected with CLC-7-cRNA. In voltage clamp experiments on ClC-7-cRNA-injected oocytes, no current changes were detected at normal pH (7.4). However, acidification of the Ringer solution to pH values between 6 and 4 revealed strong currents which reversed at about -15 mV (30 mV positive to the normal resting potential) and showed strong outward rectification. We therefore suggest that ClC-7 in oocytes is a functional chloride current at acidic pH. Since ClC-7 is also found in neuronal tissues and was upregulated in a rat pain model, we suggest a role of CLC-7 also for nociception and pain.