["Volume-dependent" form of hypertension].

Extracellular, intravascular and interstitial fluid volumes were measured in 67 patients with essential hypertension, Stage II, using Na82 Br and I131-albumin dilution techniques. Simultaneously, central hemodynamic parameters were examined, and renin activity and plasma aldosterone were assayed radioimmunologically. Clinical, hemodynamic and biochemical patterns of the hyperhydration-hypervolemic essential hypertension are described. A reverse dependence has been noted between total peripheral resistance and circulating plasma volume in normovolemic and hypovolemic hypertension. The coefficient reflecting the ratio between plasma and interstitial fluid volumes suggests an adaptive redistribution of fluid into interstitial space in some patients.