Effect of inhaled heparin on water-induced bronchoconstriction in allergic asthmatics.
OBJECTIVE
The aim of this study was to investigate the effect of inhaled heparin on bronchoconstriction induced by ultrasonically nebulised distilled water (UNDW) in allergic asthmatics.


METHODS
Eight atopic asthmatics, hyperresponsive to UNDW, were selected for this randomised, placebo-controlled, crossover double-blind study. On two consecutive days, these subjects underwent a UNDW challenge 45 min after inhaling aerosolised heparin (1000 U/kg) or placebo.


RESULTS
Neither heparin nor placebo had a significant effect on base-line forced expiratory volume in 1 s (FEV1), but heparin significantly attenuated UNDW-induced bronchoconstriction, as shown by its efficacy in preventing the decreases in FEV1 produced by all doses of water (in comparison with placebo: P < 0.05 after 2 ml water; P < 0.01 after 4, 8 and 16 ml water).


CONCLUSIONS
Inhaled heparin is able to exert a protective effect against the bronchoconstrictive response to UNDW in allergic asthmatics, and this action is likely due to inhibition of mast cell degranulation.
Tranfa
C M
CM
Dipartimento di Medicina Sperimentale e Clinica, Università di Catanzaro Magna Graecia, Italy.
Vatrella
A
A
Parrella
R
R
Pelaia
G
G
Bariffi
F
F
Marsico
S A
SA
D000280:Administration, Inhalation; D000328:Adult; D000704:Analysis of Variance; D000925:Anticoagulants / Q000008:administration & dosage* / Q000627:therapeutic use; D001249:Asthma / Q000188:drug therapy / Q000503:physiopathology*; D016084:Bronchoconstriction / Q000187:drug effects*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006493:Heparin / Q000008:administration & dosage* / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D014867:Water / Q000009:adverse effects
D000925:Anticoagulants; D014867:Water; D006493:Heparin