Abstract
The furosemide- and bumetanide-sensitive component of the 86Rb+ uptake into primary cultures of rat astrocytes was fully dependent on the simultaneous presence of Na+ and Cl- in the incubation mixture and is therefore most likely an Na+/K+/Cl- co-transporter. As expected for such a co-transporter, its activity is insensitive to 0.1 mM amiloride and to 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid, and of the tested anions, only Br- could partly replace Cl-. The K0.5 values for K+, Na+ and Cl- activation were 2.7, 35 and 40 mM, respectively. The activity of the co-transporter was stimulated 1.5-times in hyperosmolar (500 mosM) medium.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Amiloride / pharmacology
-
Animals
-
Astrocytes / metabolism*
-
Biological Transport / drug effects
-
Bumetanide / pharmacology
-
Carrier Proteins / metabolism*
-
Cells, Cultured
-
Chlorides / metabolism*
-
Furosemide / pharmacology
-
Ion Channels / metabolism
-
Ouabain / pharmacology
-
Potassium / metabolism*
-
Rats
-
Rats, Inbred Lew
-
Rubidium Radioisotopes
-
Sodium / metabolism*
-
Sodium-Potassium-Chloride Symporters
-
Sodium-Potassium-Exchanging ATPase / metabolism
Substances
-
Carrier Proteins
-
Chlorides
-
Ion Channels
-
Rubidium Radioisotopes
-
Sodium-Potassium-Chloride Symporters
-
Bumetanide
-
Ouabain
-
Amiloride
-
Furosemide
-
Sodium
-
Sodium-Potassium-Exchanging ATPase
-
Potassium