Preliminary characterization of an Na+,K+,Cl- co-transport activity in cultured human astrocytes.
We have studied the potassium uptake using 86Rb+ into monolayers of secondary cultures of human astrocytes prepared from cerebral hemispheres of a 4-month-old fetus. With the use of inhibitors we could attribute 30-40% of the 86Rb+ uptake to an Na+,K+-ATPase, 50-60% to an anion-cation co-transporter and 10% to potassium leak channels. The anion-cation co-transporter was dependent on the simultaneous presence of both sodium and chloride in the incubation medium and is therefore most likely an Na+,K+,Cl- co-transporter. This is the first evidence of such an Na+,K+,Cl- co-transport in human astrocytes.
D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D002463:Cell Membrane Permeability; D002478:Cells, Cultured; D002712:Chlorides / Q000378:metabolism*; D005333:Fetus; D006801:Humans; D051379:Mice; D011188:Potassium / Q000378:metabolism*; D051381:Rats; D012413:Rubidium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D013045:Species Specificity
D002712:Chlorides; D012964:Sodium; D012413:Rubidium; D011188:Potassium