Histamine release into cracheal lumen and bronchial reactivity

Abstract
The influence of tracheal lavage with an allergen on the airway response to bronchial challenge with histamine, acetylcholine, and ascaris extract was investigated in 36 dogs. High histamine concentrations were measured in the tracheal solution after lavage with allergen. This amine, released on the mucosal surface, was observed in only very small concentrations in the circulation. Airway response to acetylcholine inhalation was significantly increased after tracheal lavage with allergen. This hyperreactivity of the lower airways induced by tracheal lavage with an allergen suggests that a reflex mechanism is involved. After histamine inhalation a significantly larger antigen-induced histamine release to tracheal lumen was observed. No influence on airway response was found after tracheal lavage with H2O.