Effect of glucose intake on human leucocyte 86Rb influx and [3H]-ouabain binding.

86Rb influx and [3H] ouabain binding by human leucocytes were measured in eight normal nonobese fasting subjects before and after a challenge with 75 g glucose orally. The mean ouabain-sensitive 86Rb influx increased significantly from 194 to 283 mmol/kg protein/h (P less than .01), and [3H]-ouabain binding increased from 236 to 403 fmol/mg protein. The mean plasma potassium concentration fell from 4.2 to 3.9 mmol/L (P less than .05). Following intravenous glucose infusion, the median 86Rb transport increased from 186 to 267 mmol/kg protein/h, while median plasma potassium concentration fell from 4.3 to 3.9 mmol/L. Therefore, glucose intake acutely increases Na-K ATPase units, stimulates potassium (Rb) transport, and causes a concomitant fall in plasma potassium concentrations. Nutritional intake is probably an important determinant of Na-K ATPase units and activity in the human leucocyte.