The pathophysiology of rhinitis. II. Assessment of the sources of protein in histamine-induced nasal secretions.

Nasal provocation tests were performed on nine atopic and 15 nonatopic subjects in order to assess the sources of protein in histamine-induced secretions and to examine the bilateral secretory response to unilaterally applied topical histamine (the nasonasal reflex). Nasal lavages were assayed for the following proteins: albumin, total protein, secretory IgA (sIgA), nonsecretory IgA (serum IgA), and total IgA. Histamine stimulation produced a profound ipsilateral protein secretion enriched in the serum proteins albumin and nonsecretory IgA. Histamine also produced a smaller contralateral protein secretion (about 15% as large as the ipsilateral response) which contained disproportionately elevated concentrations of the glandular protein sIgA. Topical pretreatment with chlorpheniramine (an H-1 antihistamine) completely abrogated the ipsilateral nasal secretory response to histamine. Nasal pretreatment with atropine (a muscarinic antagonist) had no significant effect on ipsilateral nasal secretion and did not alter the capacity of histamine to stimulate contralateral secretions (the nasonasal reflex). Histamine therefore stimulates secretion by both a direct action that increases plasma protein extravasation and by an indirect reflex mechanism that stimulates glandular secretion.