IONIC EFFECTS ON GLUCOSE TRANSPORT AND METABOLISM BY ISOLATED MOUSE FAT CELLS INCUBATED WITH OR WITHOUT INSULIN .2. EFFECT OF REPLACEMENT OF K+ AND OF OUABAIN

1. 1. This report deals with the effects of K+ and of ouabain on the metabolism of glucose by isolated mouse fat cells. 2. 2. In the absence of insulin, both K+ lack and the presence of ouabain increased glucose uptake and metabolism. These effects were present at various concentrations of glucose and were reversible. 3. 3. In the presence of amounts of insulin sufficient for near-maximal stimulation of glucose metabolism, neither K+ lack nor ouabain had any significant effect. 4. 4. Intracellular K+ content was decreased by incubation in medfium with low K+ concentrations or containing ouabain. These results were the same, whether insulin was present in the incubation medium or not. 5. 5. A carrier system forming a ternary complex with glucose and K+ and/or Na+ is postulated. © 1969.