J Garrigo, I Danta and T Ahmed
Division of Pulmonary Disease, University of Miami School of Medicine, Mount Sinai Medical Center, Miami Beach, Florida 33140, USA.

We have previously shown that heparin attenuates allergic bronchoconstriction in sheep, inhibits anti-IgE mediated histamine release in isolated mast cells, and prevents the bronchoconstrictor response in subjects with exercise-induced asthma (EIA). The purpose of the present study was to determine the pharmacokinetics of anti- asthmatic activity of inhaled heparin in EIA and compare it with cromolyn sodium, a mast cell stabilizing agent with established efficacy in EIA. Nine subjects with a history of EIA were studied on 10 different experiment days. After obtaining baseline pulmonary functions on day 1, subjects performed a standardized exercise challenge to document the presence of EIA. While monitoring minute ventilation and heart rate, exercise challenge was performed on a treadmill with increasing workload, until 85% of predicted maximum heart rate was achieved. The subjects then continued the exercise at that workload for 10 min. EIA was assessed by measurements of specific airway conductance (SGaw) before and after exercise. On experiment days 2-10, the exercise challenge was performed after the subjects inhaled 4 ml of either heparin (20,000 u/ml), cromolyn (20 mg), or placebo solutions with increasing pretreatment intervals of 15 min, 1 h, 3 h, or 6 h in a single-blind, randomized fashion. Maximum decreases in SGaw (mean +/- SE) at 3 to 5 min after exercise on control (39 +/- 2.1%) and placebo (37 +/- 2.6%) days were reproducible. Heparin and cromolyn had no effect on baseline SGaw but attenuated the EIA in a time-dependent fashion. Heparin inhibited the bronchoconstrictor responses to exercise by 58%, 78%, and 67% (p < 0.05) when nebulized 15 min, 1 h and 3 h, respectively, before exercise; cromolyn attenuated the responses by 37%, 46%, and 41%, respectively, (p < 0.05). Although heparin offered greater protection than cromolyn (at 1 to 3 h), both agents were ineffective when administered 6 h before exercise. These data demonstrate that inhaled heparin prevents EIA for up to 3 h and is more effective than cromolyn.

This article has been cited by other articles:

				M. B. Shirk, K. R. Donahue, and J. Shirvani Unlabeled uses of nebulized medications. Am. J. Health Syst. Pharm., September 15, 2006; 63(18): 1704 - 1716. [Abstract] [Full Text] [PDF]

				J. P. Parsons and J. G. Mastronarde Exercise-Induced Bronchoconstriction in Athletes Chest, December 1, 2005; 128(6): 3966 - 3974. [Abstract] [Full Text] [PDF]

				J. Xu, P. W. Park, F. Kheradmand, and D. B. Corry Endogenous Attenuation of Allergic Lung Inflammation by Syndecan-1 J. Immunol., May 1, 2005; 174(9): 5758 - 5765. [Abstract] [Full Text] [PDF]

				A. S. Niven and G. Argyros Alternate Treatments in Asthma Chest, April 1, 2003; 123(4): 1254 - 1265. [Full Text] [PDF]

				K.E. Bendstrup, J. Gram, and J.I. Jensen Effect of inhaled heparin on lung function and coagulation in healthy volunteers Eur. Respir. J., April 1, 2002; 19(4): 606 - 610. [Abstract] [Full Text] [PDF]

				R. SUZUKI and A. N. FREED Heparin Inhibits Hyperventilation-Induced Late-Phase Hyperreactivity in Dogs Am. J. Respir. Crit. Care Med., January 1, 2002; 165(1): 27 - 33. [Abstract] [Full Text] [PDF]

				R. SUZUKI and A. N. FREED Heparin Inhibits Eicosanoid Metabolism and Hyperventilation-induced Bronchoconstriction in Dogs Am. J. Respir. Crit. Care Med., June 1, 2000; 161(6): 1850 - 1854. [Abstract] [Full Text]

				T. Ahmed, J. Ungo, M. Zhou, and C. Campo Inhibition of allergic late airway responses by inhaled heparin-derived oligosaccharides J Appl Physiol, May 1, 2000; 88(5): 1721 - 1729. [Abstract] [Full Text] [PDF]

				K. E. BENDSTRUP, C. B. CHAMBERS, J. I. JENSEN, and M. T. NEWHOUSE Lung Deposition and Clearance of Inhaled 99mTc-Heparin in Healthy Volunteers Am. J. Respir. Crit. Care Med., November 1, 1999; 160(5): 1653 - 1658. [Abstract] [Full Text]

				T. AHMED, B. J. GONZALEZ, and I. DANTA Prevention of Exercise-induced Bronchoconstriction by Inhaled Low-molecular-weight Heparin Am. J. Respir. Crit. Care Med., August 1, 1999; 160(2): 576 - 581. [Abstract] [Full Text]

				C. Campo, J. F. Molinari, J. Ungo, and T. Ahmed Molecular-weight-dependent effects of nonanticoagulant heparins on allergic airway responses J Appl Physiol, February 1, 1999; 86(2): 549 - 557. [Abstract] [Full Text] [PDF]

				J. F. MOLINARI, C. CAMPO, S. SHAKIR, and T. AHMED Inhibition of Antigen-induced Airway Hyperresponsiveness by Ultralow Molecular-weight Heparin Am. J. Respir. Crit. Care Med., March 1, 1998; 157(3): 887 - 893. [Abstract] [Full Text] [PDF]

				J. Martinez-Salas, R. Mendelssohn, W. M. Abraham, B. Hsiao, and T. Ahmed Inhibition of allergic airway responses by inhaled low-molecular-weight heparins: molecular-weight dependence J Appl Physiol, January 1, 1998; 84(1): 222 - 228. [Abstract] [Full Text] [PDF]