Effect of dexamethasone on A23187-induced airway responses in the guinea pig.
We examined the effect of dexamethasone on A23187-induced bronchospasm, pulmonary inflammation and airway responses to substance P. Guinea pigs, dosed orally once a day for 4 days with dexamethasone (3.0, 10.0 or 30.0 mg/kg) or saline, were exposed to an aerosol of A23187 for 12 min or until labored breathing began. Postmortem pulmonary gas trapping was used as an indicator of in vivo airway obstruction and changes in bronchial responses. Dexamethasone did not alter airway obstruction or inflammation 1 h after A23187 exposure. However, dexamethasone reduced the enhanced airway responses to substance P and bronchiolar/peribronchiolar inflammation 24 h post-A23187. It is possible that glucocorticosteroid suppression of A23187-induced pulmonary inflammation was important in reducing the increased airway responses to substance P.
Stengel
P W
PW
Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285.
Bendele
A M
AM
Cockerham
S L
SL
Silbaugh
S A
SA
D000280:Administration, Inhalation; D000284:Administration, Oral; D000402:Airway Obstruction / Q000188:drug therapy; D000403:Airway Resistance / Q000187:drug effects; D000818:Animals; D016535:Bronchial Hyperreactivity / Q000188:drug therapy*; D001986:Bronchial Spasm / Q000139:chemically induced / Q000188:drug therapy*; D000001:Calcimycin / Q000494:pharmacology*; D003907:Dexamethasone / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D004417:Dyspnea / Q000188:drug therapy*; D006168:Guinea Pigs; D008168:Lung / Q000187:drug effects; D008297:Male; D011659:Pulmonary Gas Exchange / Q000187:drug effects; D013373:Substance P / Q000494:pharmacology
D013373:Substance P; D000001:Calcimycin; D003907:Dexamethasone