Isoproterenol Sensitivity and Total Body Clearance of Propranolol in Hypertensive Patients

The isoproterenol sensitivity (dose-response curve) and the total body clearance of propranolol were measured in 80 men including 15 normal subjects and 65 essential hypertensive patients (20 borderline and 45 permanent hypertensives). The critical dose of isoproterenol was found to be directly correlated to weight (P less than 0.01), age (P less than 0.001), and basal diastolic arterial pressure (P less than 0.001). A partial correlation coefficient study showed that the diastolic arterial pressure was of greater influence than weight and age. The total body clearance of propranolol was inversely related to the basal diastolic arterial pressure (P less than 0.0001) in hypertensive patients. The study provides evidence that the level of basal diastolic arterial pressure could influence the beta-receptor responsiveness and the beta-adrenergic blockade in hypertensive patients.