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. …