TY - JOUR
T1 - Effects of inhaled heparin on immunologic and nonimmunologic bronchoconstrictor responses in sheep
AU - Ahmed, T.
AU - Abraham, W. M.
AU - D'Brot, J.
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1992
Y1 - 1992
N2 - The glycosaminoglycan heparin has been shown to block inositol triphosphate (IP3) receptors in various tissues. Because IP3 is one of the pathways involved in stimulus-secretion coupling in mast cells, it is possible that heparin may inhibit airway anaphylaxis. Thus, the purpose of the present investigation was to study the effect of inhaled heparin on immunologically and nonimmunologically induced bronchoconstriction in allergic sheep. Specific lung resistance (SRL) was measured in 15 sheep allergic to Ascaris suum antigen, before and after inhalation challenge with the specific antigen, compound 48/80, histamine, and carbachol. On a different day, the animals were pretreated with inhaled heparin and airway challenges with the antigen and agonists were repeated. Antigen alone increased SRL by 367 ± 119% (mean ± SE) above baseline (p < 0.05). Inhaled heparin had no effect on baseline SRL, but attenuated antigen-induced bronchoconstriction in a dose-dependent fashion: mean SRL increased by 313 ± 87, 151 ± 69, and 24 ± 20% above baseline with 100, 300, and 1,000 U/kg of heparin, respectively. Inhaled benzyl alcohol preservative, dextran sulfate, and de-N-sulfated heparin failed to inhibit antigen-induced bronchoconstriction. The dose of heparin (1,000 U/kg) that completely blocked antigen-induced bronchoconstriction also attenuated the bronchoconstriction induced by compound 48/80 (ΔSRL = 374 ± 72 versus 35 ± 12%), but failed to block the bronchoconstrictor effects of histamine and carbachol. These data suggest that inhaled heparin prevents bronchoconstrictor responses induced by stimuli that produce immunologic and nonimmunologic mast-cell degranulation in sheep, without attenuating agonist-induced bronchoconstriction. This action of heparin may be related to modulation of mast-cell mediator release rather than inhibition of airway smooth muscle contraction.
AB - The glycosaminoglycan heparin has been shown to block inositol triphosphate (IP3) receptors in various tissues. Because IP3 is one of the pathways involved in stimulus-secretion coupling in mast cells, it is possible that heparin may inhibit airway anaphylaxis. Thus, the purpose of the present investigation was to study the effect of inhaled heparin on immunologically and nonimmunologically induced bronchoconstriction in allergic sheep. Specific lung resistance (SRL) was measured in 15 sheep allergic to Ascaris suum antigen, before and after inhalation challenge with the specific antigen, compound 48/80, histamine, and carbachol. On a different day, the animals were pretreated with inhaled heparin and airway challenges with the antigen and agonists were repeated. Antigen alone increased SRL by 367 ± 119% (mean ± SE) above baseline (p < 0.05). Inhaled heparin had no effect on baseline SRL, but attenuated antigen-induced bronchoconstriction in a dose-dependent fashion: mean SRL increased by 313 ± 87, 151 ± 69, and 24 ± 20% above baseline with 100, 300, and 1,000 U/kg of heparin, respectively. Inhaled benzyl alcohol preservative, dextran sulfate, and de-N-sulfated heparin failed to inhibit antigen-induced bronchoconstriction. The dose of heparin (1,000 U/kg) that completely blocked antigen-induced bronchoconstriction also attenuated the bronchoconstriction induced by compound 48/80 (ΔSRL = 374 ± 72 versus 35 ± 12%), but failed to block the bronchoconstrictor effects of histamine and carbachol. These data suggest that inhaled heparin prevents bronchoconstrictor responses induced by stimuli that produce immunologic and nonimmunologic mast-cell degranulation in sheep, without attenuating agonist-induced bronchoconstriction. This action of heparin may be related to modulation of mast-cell mediator release rather than inhibition of airway smooth muscle contraction.
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U2 - 10.1164/ajrccm/145.3.566
DO - 10.1164/ajrccm/145.3.566
M3 - Article
C2 - 1546836
AN - SCOPUS:0026596865
VL - 145
SP - 566
EP - 570
JO - American Journal of Respiratory and Critical Care Medicine
JF - American Journal of Respiratory and Critical Care Medicine
SN - 1073-449X
IS - 3
ER -