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 < 0.95 after 2 ml water, P < 0.01 after 4, 8 and 16 ml water). Conclusion: 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.
Effect of inhaled heparin on water-induced bronchoconstriction in allergic asthmatics.
VATRELLA, Alessandro;
2001-01-01
Abstract
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 < 0.95 after 2 ml water, P < 0.01 after 4, 8 and 16 ml water). Conclusion: 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
