Single and combined therapy for systemic hypertension with propranolol, hydralazine and hydrochlorothiazide: hemodynamic and neuroendocrine mechanisms of action

Abstract The antihypertensive mechanisms of single and combined therapy with a β-adrenergic antagonist (propranolol) and a vasodilator (hydralazine) were investigated in 9 patients with moderately severe hypertension, who were receiving maintenance diuretic (hydrochlorothiazide) treatment. Hemodynamic and neuroendocrine responses were determined at rest and during lower body negative pressure, and dynamic and static exercise stress after the chronic administration of propranolol and hydralazine, given alone or in combination. All 3 drug regimens, each administered for at least 10 weeks, reduced blood pressure (p