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Eight healthy men were randomly assigned in a latin square order to receive single doses of placebo, tertatolol 5 mg, propranolol 80 mg and atenolol 100 mg at 7-day intervals. Resting heart rate and pulmonary function were measured 10 min before and over the 240 min following dosing, and then 15 min after inhalation of salbutamol 200 µg and ipratropium bromide 40 µg. The three beta-blockers caused similar reductions in resting heart rate throughout the study, whereas placebo had no effect. The three beta-blockers, like placebo, produced no significant change in pulmonary function during the 240 min after dosing. The bronchodilator response to salbutamol after atenolol and placebo was preserved, whereas it was reduced after administration of either of the non-selective beta-blockers, tertatolol and propranolol. An unequivocal response of the airways to ipratropium bromide was observed after tertatolol and propranolol, which was much greater than after atenolol. No response was observed after placebo. Thus, despite bronchial beta-blockade, by non-selective beta-blockers, bronchodilatation was definitely produced by ipratropium bromide, confirming the predominant role of the parasympathetic system in the autonomic innervation of normal human airways. [ABSTRACT FROM AUTHOR]

Seven asthmatic patients were given a single placebo tablet in a first test session and then in two subsequent double blind sessions they randomly received 400 mg bevantolol or 100 mg atenolol, with at least 2 days between each of the sessions. Neither beta-blocker had any significant effect on FVC as compared to the placebo. FEV 1, however, was significantly lower 2 and 3 h after atenolol or bevantolol; there was no significant difference between the effects of the two drugs on FEV 1. Peak expiratory flow rate was reduced by bevantolol but not by atenolol, the difference reaching significance after 3 h. Fenoterol inhalation at the end of each test session always enhanced pulmonary performance, but to a lesser extent after bevantolol than after placebo or atenolol. A slower heart rate was recorded 2, 3, and 4 h after bevantolol and 3 and 4 h after atenolol; the mean 2-h value was significantly lower with atenolol than with bevantolol. No patient suffered any adverse effect. Bevantolol may be slightly less selective than atenolol. [ABSTRACT FROM AUTHOR]