EFFECT OF ATROPINE AND ALBUTEROL AEROSOLS ON HUMAN BRONCHIAL RESPONSE TO HISTAMINE

[摘要] Whether histamine-induced bronchoconstriction in human asthmatics is mediated by the parasympathetic nervous system and involves cholinergic pathways was investigated. Inhalation challenges were performed on 14 adult asthmatic patients using the standardized procedure for inhalation challenge. The effect of pretreatment with either aerosolized atropine sulfate or albuterol, a specific .beta.-2 adrenergic agonist, was studied. The cumulative units of histamine required for induction of PD20-FEV, [a 20% or greater drop in the forced expiratory volume is from baseline] was used as the basis of comparison of the effects of these drugs. Aerosolization of sufficient atropine to effect a cholinergic blockade, as shown by inhibition of the bronchial response to inhaled methacholine, only minimally affected the bronchial response to histamine. The administration of albuterol markedly shifted the response to histamine. Although there was a significant change in the mean PD20-FEV1 to histamine following atropine blockade, this effect was small in comparison to that which could be demonstrated with a .beta. agonist. The major influence of histamine was probably not through cholinergic pathways.