Pathogenic mechanism Iae mast cell smooth muscle contraction of the bronchiole allergen allergen histamine ECF immediate asthma reaction AAI ventilation disorder PAF ECF airway obstruction by exudation Late asthma reaction lts microvascular transudation ( LAR congestion and edema of the mucosa BHR PGS injury and exfoliation of the epithelial cells exposure of nerve ending neuropeptide, substance P inflammatory cells macrophage, eosinophils and neutrophilsPathogenic mechanism • IgE、mast cell smooth muscle contraction of the bronchiole allergen allergen histamine、ECF immediate asthma reaction • • AAI ventilation disorder • • • PAF • ECF airway obstruction by exudation • Late asthma • reaction LTS microvascular transudation • （LAR） congestion and edema of the mucosa • BHR • PGS • injury and exfoliation of the epithelial cells • exposure of nerve ending neuropeptide、substance P • inflammatory cells • （macrophage、eosinophils and neutrophils） •