[The relationship between interleukin-8 and airway hyperresponsiveness].
OBJECTIVE
To explore the relationship between interleukin-8 (IL-8) and airway hyperresponsiveness (AHR) of asthma.


METHODS
IL-8 at a dose of 0.5 microgram/kg or 5 micrograms/kg was administered intranasally to guinea-pigs twice a week for 3 weeks. 24 hours after the last administration, airway responsiveness was measured as an overall index of airway response to increasing concentrations of inhaled histamine (25, 50, 100 and 200 micrograms/ml) and the numbers of different inflammatory cells in bronchoalveolar lavage fluid (BALF) was counted.


RESULTS
The IL-8 treatment significantly enhanced airway responsiveness to histamine in a dose-dependent manner (P < 0.05 or 0.01) and induced a significant influx of neutrophils in BALF (P < 0.01), and there are many neutrophils within airway wall but not control animals treated with phosphate buffered saline (PBS).


CONCLUSIONS
The IL-8 given into the airways can produce neutrophil inflammation of the airways and induce AHR, it may play an important role in asthma, especially in the development of AHR.
Lü
K
K
Xijing Hospital Fourth Military Medical University, Xi'an.
Qi
H
H
Wang
W
W
D000818:Animals; D001249:Asthma / Q000139:chemically induced* / Q000473:pathology; D016535:Bronchial Hyperreactivity / Q000139:chemically induced* / Q000473:pathology; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology*; D006168:Guinea Pigs; D016209:Interleukin-8; D007958:Leukocyte Count; D008297:Male; D009504:Neutrophils / Q000187:drug effects*
D016209:Interleukin-8