[Erythrocyte cation transport in arterial hypertension: interrelation with the renin-angiotensin-aldosterone system and the atrial natriuretic factor].

Red cell membrane Na(+)-K+ transport systems, renin-angiotensin-aldosterone system (RAAS) and atrial natriuretic factor (ANF) were studied in a group of 50 mild essential hypertensive patients (n = 25 for each group) age, sex and blood pressure matched. Na(+)-K+ ATPase and intracellular Na+ (Na+ i) were significantly different between the two groups (p less than 0.01). A slight difference was also seen for the Na(+)-K+ cotransport (p less than 0.05) as a likely consequence of the differences in the methodology of Na+ charge to study its efflux from the red cells in vitro. A negative correlation (r = -0.47, p less than 0.01) was observed between ANF and Na(+)-K+ cotransport suggesting an interrelationship of the two systems in the homeostasis in body fluid and electrolytes.