Characterization of the chloride conductance in porcine renal brush-border membrane vesicles.
The chloride conductance in brush-border membrane vesicles prepared from pig kidney cortex was investigated using a light-scattering assay, anion-diffusion-potential-dependent Na+-D-glucose cotransport and 36Cl- influx. K+-diffusion-potential-driven salt exit from, or entry into, the vesicles was slow in the presence of gluconate, SO42- and F-, intermediate with Cl- and Br-, and fast with I-, NO3-, and SCN-. Stimulation of Na+-D-glucose uptake followed a similar anion sequence. Conductive Cl- flux had a low activation energy and was inhibited by suphhydryl reagents, the stilbene disulphonates 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulphonate (SITS) and 4, 4'-diisothiocyanato-2,2'-disulphonate (DIDS), and the arylaminobenzoates diphenylamine-2-carboxylic acid (DPC) and 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB). Intravesicular Ca2+ and extravesicular nucleotides were without effect on conductive Cl- flux. These characteristics tentatively exclude some known Cl- channels and leave members of the ClC family as possible candidates responsible for the Cl- conductance in brush-border membranes.
Krick
W
W
Abteilung Vegetative Physiologie und Pathophysiologie, Zentrum Physiologie und Pathophysiologie, Humboldtallee 23, D-37073 Göttingen, Germany.
Dölle
A
A
Hagos
Y
Y
Burckhardt
G
G
D000818:Animals; D000838:Anions; D001692:Biological Transport; D001965:Bromides / Q000494:pharmacology; D018118:Chloride Channels / Q000502:physiology*; D002712:Chlorides / Q000378:metabolism / Q000494:pharmacology; D004553:Electric Conductivity; D005459:Fluorides / Q000494:pharmacology; D005942:Gluconates / Q000494:pharmacology; D005947:Glucose / Q000378:metabolism; D007454:Iodides / Q000494:pharmacology; D007672:Kidney Cortex / Q000187:drug effects / Q000648:ultrastructure*; D008871:Microvilli / Q000502:physiology*; D009566:Nitrates / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D013431:Sulfates / Q000494:pharmacology; D013439:Sulfhydryl Reagents / Q000494:pharmacology; D013552:Swine; D013861:Thiocyanates / Q000494:pharmacology
D000838:Anions; D001965:Bromides; D018118:Chloride Channels; D002712:Chlorides; D005942:Gluconates; D007454:Iodides; D009566:Nitrates; D013431:Sulfates; D013439:Sulfhydryl Reagents; D013861:Thiocyanates; D012964:Sodium; D005947:Glucose; D005459:Fluorides; C030691:gluconic acid; D011188:Potassium