Effects of β-Adrenergic Receptor Blockade on Airway Conductance and Lung Volume in Normal and Asthmatic Subjects

Ten normal and five asthmatic subjects were given intravenous injections of 10 ml. of 0·9% saline with and without 10 mg. of propranolol, and specific airway conductance was followed in a whole-body plethysmograph. Saline alone had no significant effect on conducatance in either group of subjects. Propranolol had no significant effect on conductance in normal subjects, but caused a mean fall of 34·9% in the asthmatics.