DECREASED GRANULOCYTE RESPONSE TO ISOPROTERENOL IN ASTHMA DURING UPPER RESPIRATORY-INFECTIONS

Abstract

Isoproterenol inhibits zymosan-stimulated release of lysosomal enzymes from granulocytes. Using this as an in vitro cell model to study .beta.-adrenergic response, granulocyte reaction to isoproterenol was examined in asthma. There was a significantly decreased response to isoproterenol (10-7-10-5M) in patients with mild asthma who had not taken bronchodilators for 2 wk before study and in patients with severe asthma requiring bronchodilators and corticosteroids. During respiratory infections that provoked asthma attack, the granulocyte response to isoproterenol was further decreased. The change in granulocyte response to isoproterenol may reflect a similar change in .beta.-adrenergic tone of airways and provide 1 explanation for asthma during colds.