title: The effect of Cys LT1 receptor blockade on airway responses to allergen.
abstract: OBJECTIVE
  To evaluate the effect of a potent experimental leukotriene receptor antagonist, MK-571, on airway responses to inhaled allergen.
  
  
  METHODS
  Randomized, double-blind, placebo-controlled, crossover trial.
  
  
  METHODS
  Clinical research center.
  
  
  METHODS
  Eight male volunteers with allergic asthma.
  
  
  METHODS
  An intravenous loading dose was followed by an 8-hour infusion of MK-571 or placebo, with a 7- to 14-day washout between treatments. Allergen challenge was performed after the loading dose and a histamine challenge was performed before and 24 hours after allergen.
  
  
  RESULTS
  Forced expiratory volume in 1 second was measured serially. MK-571 provided about 50% protection during maximum early and late responses compared with placebo (p=0.005), but airway obstruction persisted 8-24 hours after allergen on both treatment days. Airway responsiveness to histamine was not significantly attenuated at 24 hours.
  
  
  CONCLUSIONS
  Blocking Cys LT1 receptors for 8 hours attenuated the early and late responses but did not interrupt the cascade of events leading to subsequent allergen-induced airway obstruction and hyperreactivity.
authors.affiliation: College of Pharmacy and The Department of Pediatrics, University of Florida, Gainesville 32610-0486, USA.
authors.forename: L
authors.initials: L
authors.lastname: Hendeles
authors.forename: D
authors.initials: D
authors.lastname: Davison
authors.forename: E
authors.initials: E
authors.lastname: Harman
authors.forename: J M
authors.initials: JM
authors.lastname: Sherman
mesh_terms: D000328:Adult; D000402:Airway Obstruction / Q000517:prevention & control*; D000485:Allergens / Q000276:immunology*; D016535:Bronchial Hyperreactivity / Q000517:prevention & control*; D018592:Cross-Over Studies; D003545:Cysteine / Q000037:antagonists & inhibitors*; D004311:Double-Blind Method; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D020024:Leukotriene Antagonists / Q000494:pharmacology*; D015289:Leukotrienes; D008297:Male; D011422:Propionates / Q000494:pharmacology*; D011804:Quinolines / Q000494:pharmacology*
chemical_list: D000485:Allergens; D020024:Leukotriene Antagonists; D015289:Leukotrienes; D011422:Propionates; D011804:Quinolines; C112381:cysteinyl-leukotriene; C059141:verlukast; D003545:Cysteine