Thallium uptake by canine iliac arteries.
Most of the thallium uptake by canine iliac arteries (70%) was inhibited by ouabain. The component sensitive to ouabain was significantly increased by incubating tissues in K+-free solution and reduced by low temperatures, metabolic inhibitors, and loading with lithium. The apparent Km for thallium for the ouabain-sensitive uptake was 0.47 +/- 0.046 mM. External K+ inhibited thallium uptake and the apparent Ki was estimated to be 6.5 mM. Thallium thus appears to have a greater affinity for the ouabain-sensitive components. The residual component of thallium uptake was unaffected by maneuvers that affected the ouabain-sensitive uptake, which thus appears to be a suitable indicator of Na+ pump activity in vascular smooth muscle.
D000818:Animals; D001693:Biological Transport, Active; D004285:Dogs; D005260:Female; D007083:Iliac Artery / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D011868:Radioisotopes; D012964:Sodium / Q000378:metabolism*; D013793:Thallium
D011868:Radioisotopes; D010042:Ouabain; D012964:Sodium; D013793:Thallium; D011188:Potassium