Kinetics of cellular influx and histamine release in normal human bronchi.
Inhalation of certain substances can induce bronchial inflammation followed by bronchoconstriction or bronchial hyperreactivity. We have developed a model of airway inflammation and bronchoconstriction induced by an aqueous extract of cotton bracts (CBE) in which the severity of flow rate reduction correlates with the presence of bronchoalveolar neutrophils. In the current study normal human volunteers underwent local bronchial instillation of CBE. Bronchial lavage histamine concentrations and cellular populations were determined at time intervals after local challenge. In addition, bronchial biopsies were obtained after CBE instillation, and the degree of subepithelial inflammation was quantitated. We report that lavage of bronchi locally exposed to CBE contains 1) greater histamine concentrations 4 min after challenge compared with lavage from saline-challenged bronchi and 2) concentrations of eosinophils and macrophages that are greater than control lavage 8 min after exposure. Bronchial biopsies taken after CBE instillation also demonstrated a variable degree of subepithelial granulocyte infiltration that correlated with the global bronchoconstricting response to CBE assessed on a separate day. These studies suggest that inflammation can develop rapidly in normal human bronchi and may precede significant flow rate reductions by greater than 1 h.
Cooper
J A
JA
Pulmonary Section, West Haven Veterans Administration Medical Center 06516.
Merrill
W W
WW
Buck
M G
MG
D001706:Biopsy; D001980:Bronchi / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D003368:Gossypium; D006636:Histamine Release / Q000187:drug effects; D006801:Humans; D007700:Kinetics; D007962:Leukocytes / Q000166:cytology / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D012016:Reference Values; D007507:Therapeutic Irrigation
D010936:Plant Extracts