Abnormal Whole-Body and Cellular (Erythrocytes) Turnover of ²²Na⁺ in Normotensive Relatives of Probands with Established Essential Hypertension

1. Whole-body elimination rate of ²²Na⁺ was decreased in normotensive or borderline first-degree relatives of hypertensive probands.

2. Whole-body potassium; exchangeable sodium and urine excretion of sodium, potassium and creatinine were similar in relatives and controls.

3. Erythrocyte net influx of ²²Na⁺ was significantly increased in normotensive relatives.

4. Abnormal whole-body and cellular handling of sodium (²²Na⁺) demonstrated in relatives indicates that this abnormality may have an important role in the development of essential hypertension in man.