[Atrial natriuretic factor in patients with hypertension].

Plasma levels of atrial natriuretic factor were measured in 71 patients with essential hypertension and 13 with borderline arterial hypertension by using radioimmunoassay. Higher concentrations of plasma atrial natriuretic factor were found to be dependent on hemodynamic changes in patients with Stage II hypertensive disease. There was a weaker atrial natriuretic factor-natriuresis relationship in patients with early essential hypertension. Left ventricular myocardial hypertrophy was shown to greatly affect plasma atrial natriuretic factor concentrations. There was an inverse correlation between the level of atrial natriuretic factor and the concentration of plasma aldosterone, which suggests that they might act antagonistically, affecting fluid-and-electrolyte homeostasis. The angiotensin-converting enzyme blocker enalapril maleate used as an antihypertensive agent caused a significant reduction in plasma atrial natriuretic factor concentrations.