Effect of histamine on the permeability of the nasal mucosa in vivo

Objective - Histamine is one of the chemical mediators released during the acute phase of allergic rhinitis and is considered to cause the increase in epithelial permeability observed. We tried to examine the effect of histamine on nasal mucosal permeability in vivo. Material and methods - Histamine at different concentrations was administered to the nostrils of healthy subjects and the nasal transepithelial potential difference (PD) was measured. We also examined nasal mucosal permeability by means of a histochemical technique using horseradish peroxidase (HRP) in guinea pigs. Results - Administration of 10-1 M histamine significantly reduced the nasal PD in healthy subjects. After administration of 5.4 × 10-1 M histamine to the noses of guinea pigs, most of the intercellular spaces showed positive reactions to HRP and this effect was significantly inhibited by pretreatment with mepyramine and the antihistamine bepotastine besilate. Conclusion - These results indicate that histamine plays an important role in the change in mucosal permeability observed in allergic rhinitis in vivo via the histamine H1 receptor