Effect of β-adrenergic receptor blockade on atrial natriuretic peptide in essential hypertension

Abstract

Plasma levels of atrial natriuretic peptide (ANP) were measured in 32 untreated subjects with essential hypertension and in 31 patients undergoing long-term treatment with β-blockers. Patients receiving β-blockers had significantly higher mean plasma ANP levels (72.0 ± 36.0 [SD] pg/ml) than did untreated hypertensive subjects (39.8 ± 15.8 pg/ml; p < 0.01) and healthy normiotensive controls (33.9 ± 16.6 pg/ml; n = 61, p < 0.01), while the mean plasma ANP concentration in untreated hypertensive subjects was not statistically different from that in control subjects. Administration of atenolol, 50 mg/day, for 4 weeks to 10 untreated subjects resulted in a significant (p < 0.001) rise in plasma ANP levels (from 38.8 ± 9.5 to 68.7 ± 20.6 pg/ml). In 31 patients undergoing long-term treatment with β-blockers, multivariate regression analysis revealed that age, pretreatment mean blood pressure, and plasma concentration of cyclic 3',5'-guanosine monophosphate (cGMP) were significant predictors of plasma ANP levels. These results suggest that β-adrenergic receptor blockade in patients with essential hypertension elevates plasma ANP levels with a concomitant rise in cGMP concentrations, and that increased ANP in plasma may play a role in the compensatory mechanism that operates in response to β-adrenergic receptor blockade.