skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Photoinactivation of sodium-potassium-chloride cotransport in LLC-PK1/Cl 4 cells by bumetanide

Journal Article · · Am. J. Physiol.; (United States)
OSTI ID:5654165

Rb+ uptake into LLC-PK1/Cl 4 cells can be subdivided into three components: 1) ouabain-sensitive uptake, 2) bumetanide-sensitive uptake, and 3) ouabain- and bumetanide-insensitive uptake. Exposure of cells to near-UV light in the presence of low concentrations of bumetanide produces a specific, irreversible inhibition of the bumetanide-sensitive uptake component, while not affecting the other two uptake components. Irreversible inhibition of bumetanide-sensitive transport is observed when measuring either cellular uptake or efflux and also when measuring /sup 86/Rb+ uptake into membrane vesicles. The irreversible inhibition is both concentration and time dependent and is blocked under conditions where the interaction of bumetanide with the Na+-K+-Cl- cotransporter is disturbed. We conclude that bumetanide, at low concentrations, can specifically and irreversibly inhibit the Na+-K+-Cl- cotransporter of LLC-PK1/Cl 4 cells. We suggest that this irreversible inhibition is the result of the photoactivation of an ether linkage in the bumetanide molecule, leading to a covalent binding of bumetanide to the Na+-K+-Cl- cotransporter.

Research Organization:
Max-Planck-Institut fuer Systemphysiologie, Dortmund, Germany, F.R.
OSTI ID:
5654165
Journal Information:
Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States)
Country of Publication:
United States
Language:
English

Similar Records

Characterization of a Na : K : 2Cl cotransport system in the apical membrane of a renal epithelial cell line (LLC-PK1)
Journal Article · Tue Jan 01 00:00:00 EST 1985 · J. Membr. Biol.; (United States) · OSTI ID:5654165

Bradykinin and vasopressin stimulate Na/sup +/-K/sup +/-Cl/sup -/ cotransport in cultured endothelial cells
Journal Article · Sun Jun 01 00:00:00 EDT 1986 · Am. J. Physiol.; (United States) · OSTI ID:5654165

A Na-K-Cl cotransporter in isolated rat papillary collecting duct cells
Journal Article · Tue Aug 01 00:00:00 EDT 1989 · Kidney International; (USA) · OSTI ID:5654165