Regulation of Na/K/Cl cotransport in vascular smooth muscle cells.
The regulation of Na/K/Cl cotransport was investigated in vascular smooth muscle cells. That a Na/K/Cl cotransport system exists was established by the finding that the ouabain insensitive K influx was sensitive to the "loop" diuretic bumetanide. Furthermore, bumetanide sensitive K influx was dependent upon the presence of both Na and Cl in the extracellular milieu. Bumetanide sensitive K influx was inhibited by agents which elevate cellular cyclic AMP levels, and to a lesser extent by agents which elevate cellular cyclic GMP levels. When serum, EGF or TPA was added, bumetanide sensitive K influx was enhanced. These results suggest that vascular smooth muscle cells have a ouabain insensitive, bumetanide sensitive Na/K/Cl cotransport system which is stimulated by serum, EGF or TPA and inhibited by cAMP or cGMP.
D000818:Animals; D001013:Aorta, Thoracic; D002034:Bumetanide / Q000494:pharmacology; D002352:Carrier Proteins / Q000378:metabolism*; D002460:Cell Line; D002712:Chlorides / Q000378:metabolism*; D000242:Cyclic AMP / Q000494:pharmacology; D007700:Kinetics; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism*; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism*; D051381:Rats; D012413:Rubidium; D012964:Sodium / Q000378:metabolism*; D028021:Sodium-Potassium-Chloride Symporters
D002352:Carrier Proteins; D002712:Chlorides; D028021:Sodium-Potassium-Chloride Symporters; D002034:Bumetanide; D010042:Ouabain; D012964:Sodium; D000242:Cyclic AMP; D012413:Rubidium; D011188:Potassium