Drug effects on antigen-induced release of high molecular weight-neutrophil chemotactic activity and histamine in nasal secretion from children with allergic rhinitis.

Five children with allergic rhinitis sensitive to house dust mite as documented by skin test, radioallergosorbent test, score and nasal provocation were studied. Patients were subjected to nasal challenge with 3.125, 6.25, 12.5, and 25 protein nitrogen micrograms per disc of house dust mite antigens and nasal secretions were collected by the filter paper method. Neutrophil chemotactic activity (NCA) and histamine content of the nasal secretions were measured. NCA and histamine were released in a dose- and time-dependent manner, and no significant correlation between NCA and histamine was revealed in each subject. Pretreatment with 5.2 mg of nasal disodium cromoglycate or 0.5 micrograms of nasal adrenaline 5 minutes before provocation totally inhibited mediator release upon nasal challenge with 12.5 micrograms of house dust mite. A dose of 100 micrograms of nasal beclomethasone dipropionate 5 minutes before challenge neither inhibited clinical symptoms nor mediator release; 100 micrograms x 3 times per day of nasal beclomethasone dipropionate for 3 days, however, significantly inhibited clinical symptoms and release of both NCA (p less than 0.05) and histamine (p less than 0.05). NCA eluted as a single peak with an estimated molecular weight of 600,000. These results suggest that high molecular weight-NCA may be involved in the pathogenesis of allergic rhinitis.