Bronchial Response to Beta-Adrenergic Blockade

Abstract

ASTHMA can be defined as a disease of the bronchi producing diffuse, reversible bronchial obstruction. The bronchial tree of patients with asthma is hypersensitive to the effects of dust, cold air, histamine, methacholine and pollen extracts, so that bronchial obstruction roughly proportional to the severity of the asthma can be demonstrated after such exposures.2 3 4 5 The cause of this bronchial hypersensitivity is not known. Patients with other forms of chronic obstructive pulmonary disease or allergic rhinitis have similar but less marked bronchial sensitivity to these materials.5 , 6 A series of investigations in animals has led to the hypothesis that a partial beta-adrenergic . . .