Cl− co-transport in primary cultures of rat astrocytes (original) (raw)

The furosemide-and bumetanide-sensitive component of the S6Rb+ uptake into primary cultures of rat astrocytes was fully dependent on the simultaneous presence of Na ÷ and CI-in the incubation mixture and is therefore most likely an Na÷/K +/CI-co-transporter. As expected for such a co-transporter, its activity is insensitive to 0.1 mM amiloride and to 4-acetamido-4'-isothiocyanostiibene-2,2'.disulfonic acid, and of the tested anions, only Br-could partly replace CI-. The K0. 5 values for K ÷, Na + and C!-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.