Referenced in: none

Automatically associated channels: ClC4 , ClC5

Title: Expression of chloride channel, ClC-5, and its role in receptor-mediated endocytosis of albumin in OK cells.

Authors: Y Sasaki, J Nagai, Y Kitahara, N Takai, T Murakami, M Takano

Journal, date & volume: Biochem. Biophys. Res. Commun., 2001 Mar 23 , 282, 212-8

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/11263994

Abstract
By using Western blot and RT-PCR analyses, the expression of ClC-5, a member of the ClC family of voltage-gated chloride channels, and its mRNA was detected in OK cells. The effect of chloride channel inhibitors on receptor-mediated endocytosis of albumin was examined in OK cells and compared to that of vacuolar H(+)-ATPase inhibitors. Accumulation of fluorescein-isothiocyanate (FITC)-albumin, a receptor-mediated endocytosis marker, was inhibited by 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), a chloride channel inhibitor, in a concentration-dependent fashion. In contrast, uptake of FITC-inulin, a fluid-phase endocytosis marker, was not affected by NPPB. Other chloride channel inhibitors, 4,4'-diisothiocyanatostilbene-2-2'-disulfonic acid and diphenylamine-2-carboxylic acid, also inhibited FITC-albumin uptake. NPPB, as well as a vacuolar H(+)-ATPase inhibitor bafilomycin A(1), caused a decrease in the affinity and in the maximal velocity of FITC-albumin uptake. These results suggest that chloride channel, most likely ClC-5, plays an important role in the receptor-mediated endocytosis of albumin in OK cells.