Changes of adrenergic and muscarinic cholinergic receptors in nasal mucosa in nasal allergy.

Abstract

Receptor-binding assays were performed to evaluate the changes of beta- and alpha 1-adrenergic and muscarinic receptors in the nasal mucosa of subjects with nasal allergy and in guinea pigs sensitized with ovalbumin using radioligands 3H-DHA, 3H-prazosin and 3H-QNB, respectively. In subjects with nasal allergy, a decrease in density of beta- and alpha 1-adrenergic receptors and an increase in density of muscarinic cholinergic receptors were observed. An increase in density of muscarinic cholinergic receptors could be reproduced in the nasal mucosa of guinea pigs which were sensitized with ovalbumin and had typical hyperreactive nasal symptoms. These results indicate that the increase in the density of muscarinic receptors observed in the nasal mucosa of subjects with nasal allergy has been induced secondarily by an allergic reaction in the nasal mucosa with hyperreactive nasal symptoms, which in turn acts as an aggravating factor in the vicious circle promoting hyperreactivity of the nasal mucosa.