Effects of propranolol and atenolol on blood pressure and plasma renin activity in patients with moderate hypertension.

A double-blind crossover trial was completed in 15 patients with moderate hypertension and the effects of propranolol (Inderal) 80 mg twice a day and atenolol (Tenormin) 100 mg twice a day were assessed on blood pressure, pulse rate and plasma renin activity (PRA), while patients were maintained on 1 cyclopenthiazide tablet (Navidrex K) per day. Both agents caused a significant reduction in blood pressure and pulse rate with patients at rest and during exercise. Plasma renin activity was significantly reduced by both agents in subjects with normal and high renin levels (with PRA 2-8 ng/ml/h and greater than 8 ng/ml/h respectively). Blood pressure responses could not be correlated with renin status or reduction in pulse rate. No adverse effects were attributable to either of the two beta-adrenergic blocking agents and we concluded that a beta1-selective agent, which has the advantage of not aggravating bronchospasm, can replace the non-selective propranolol.