Familial aggregation of cation transport abnormalities and essential hypertension.

The maximal rate of activity of Na extrusion by the Na pump, Na-K outward cotransport, Na-Li countertransport and the rate constant for passive permeability to Na, K and Li were measured in the RBC of 24 normotensive subjects with both parents normotensive, 45 hypertensive subjects and 24 of their normotensive offspring. The Na extrusion by the Na pump and the passive permeability to Na, K and Li are equal. The hypertensives have significantly greater Na-Li countertransport and smaller Na-K cotransport when compared to the normotensives. Na-K cotransport and Na-Li countertransport are positively correlated, thus suggesting some relationship between the two systems. When arbitrary normal limits are set the hypertensives are divided in three groups: normal cotransport and countertransport (22.2%) high countertransport (31.1%) and low cotransport (44.4%). In nine hypertensive families studied if either alteration was observed in a hypertensive propositus, this was of the same kind as the one in case observed in any first degree relative, whether already hypertensive or young normotensive. The observed alterations are primitive to the development of hypertension and possibly related to its pathogenesis.