Atrial and Digitalis-Like Natriuretic Hormones in Essential Hypertension Under Functional Loading

To assess the relation of the two natriuretic hormones, atrial natriuretic peptide (ANP) and digitalis-like natriuretic factor (DLF), to hypertension, levels of ANP and DLF were measured under basal conditions and after salt and water loading in 31 normal subjects and 36 and 57 patients with Stage I or II essential hypertension (EH). DLF levels were higher in normal women than men; in EH-II patients, DLF levels were elevated among men but subnormal in women (P less than .02) and rose with water loading in both genders. In all groups ANP levels tended to be higher in women. Water loading increased ANP levels in EH-I patients (P less than .001) and caused less marked increases of ANP in control and EH-II women and men. ANP also tended to increase with salt loading. Both DLF and ANP were related to blood pressure in the subject groups (r = 0.75 to 0.96 and r = 0.27 to 0.75, respectively) and were also related to each other (r = 0.20 to 0.47). The role of ANP and DLF in hypertension are likely to be compensatory and directed against water-electrolyte metabolism disorders associated with elevated arterial pressure.