The Effect of Heparin on Antigen-Induced Mucus Hypersecretion in the Nasal Epithelium of Sensitized Rats

Background: Heparin is a potential anti-inflammatory drug for allergic airway inflammation. To elucidate the effects of heparin on allergic inflammation, we examined the in vivo effects of heparin on antigen-induced mucus hypersecretion and infiltration of eosinophils and neutrophils in the nasal epithelium of sensitized rats. Methods: We induced hypertrophic and metaplastic changes of goblet cells in the nasal epithelium of ovalbumin (OVA)-sensitized rats by intranasal challenge with OVA. The effects of intranasal instillation with low molecular weight heparin (LMWH; 1-1000 IU/0.1 ml) on mucus production and eosinophil/neutrophil infiltration were examined. Results: Intranasal instillation with low-dose LMWH (1-10 IU/0.1 ml) at 30 minutes before OVA instillation stimulated OVA-induced mucus production in the nasal epithelium of sensitized rats, whereas treatment with 100 IU/0.1 ml LMWH showed no effect. Intranasal instillation with high-dose LMWH (1000 IU/0.1 ml) significantly inhibited OVA-induced mucus production. Intranasal instillation with LMWH (1-1000 IU/0.1 ml) dose-dependently inhibited eosinophil and neutrophil infiltration into the rat nasal mucosa. Conclusions: These results indicate that heparin inhibits mucus hypersecretion and infiltration of eosinophils and neutrophils in allergic inflammation, though the inhibitory effect against mucus production is obtained in high-dose heparin. Intranasal instillation with high-dose heparin may provide a new therapeutic strategy for the treatment of nasal allergic inflammation.