Participation of vascular reflex in mucosal swelling in nasal allergy

A study was performed to evaluate whether vascular reflex participates in mucosal swelling in nasal allergy, by measuring changes in mucosal swelling in both nasal cavities and changes in blood flow in the bilateral inferior turbinates caused by antigenic challenge in one inferior turbinate. On unilateral challenge, the mucosa of the ipsilateral nasal cavity became swollen, with a concomitant increase in mucosal blood flow. In the contralateral nasal cavity, however, an increase in mucosal blood flow was not necessarily accompanied by mucosal swelling. An increase in mucosal blood flow on antigenic challenge was observed even in nasal mucosa, most of the parasympathetic and sympathetic innervation to which was transected by vidian neurectomy. Vascular reflex certainly participates in nasal allergy but it is not always related to mucosal swelling. Mucosal swelling in nasal allergy is considered to be caused mainly by a direct effect of chemical mediators on nasal vasculature and partly by vascular reflex.