DECREASE IN BETA-ADRENERGIC RECEPTORS OF LYMPHOCYTES IN SPONTANEOUSLYOCCURRING ACUTE ASTHMA

To clarify changes in beta-adrenergic receptor (BAR) density in sponta neously occurring acute asthma, BAR binding studies were performed on peripheral blood lymphocytes in eight asthmatic and ten normal subject s. Spirometry also was performed. Maximum binding capacity (Bmax) of B AR in acute asthma was significantly lower by 44.2 percent compared wi th that in stable asthma; FEV1/FVC ratio decreased by 23.9 percent. Th e Bmax for acute asthma also was significantly lower than that in norm al subjects. The Bmax of BAR in all subjects was significantly correla ted with FEV1/FVC ratio and percent FEV1. The percentage decrease in t he FEV1/FVC ratio and FEV1 from the stable to acute state for each ast hmatic subject did not correlate with corresponding percentage decreas e in Bmax. These data demonstrate that BAR density of lymphocytes decr eases substantially in acute asthma and, simultaneously, suggest that some factors other than the BAR mechanism contribute to the airway obs truction during acute asthma.