Effect of Changes in Dietary Sodium and Potassium on Blood Pressure and Cellular Electrolyte Handling in Young Normotensive Subjects

In a study on 22 normotensive male subjects, a change in dietary sodium intake from 29.6 +/- 6.0 to 332.5 +/- 13.9 mmol/day (mean +/- s.e.m.), over 7 days, was associated with a significant rise in supine and standing systolic blood pressure and a fall in sodium pump activity. Intracellular sodium remained constant, while intracellular potassium fell. These changes appeared to be reversed by the addition of potassium (96 mmol/day) to the high sodium diet. The 12 subjects with a family history of essential hypertension, as determined by measurement of parental blood pressure, did not differ in their response from those whose parents were normotensive.