Effects of Muscarinic Antagonists on Experimental Nasal Secretion in Guinea Pigs.

Abstract

ABSTRACT-The effects of muscarinic antagonists on acetylcholine (ACh) and histamine-induced nasal secretion were investigated in guinea pigs. Inhalations of flut ropium (0.01 to 0.3%) and atropine (0.03 to 0.3%) into the nasal cavities dose-depend ently inhibited the nasal secretion induced by ACh. The inhibitory action of flutro pium was slightly stronger than that of atropine. Inhalations of pirenzepine (0.3%) and gallamine (0.3%) had no effect on the ACh-induced nasal secretion. However, 4 DAMP dose-dependently inhibited the nasal secretion induced by ACh. Inhalations of flutropium (0.3%) and diphenhydramine (0.3%) showed a similar inhibitory action on the histamine-induced nasal secretion. These results suggest that 1) inhalation into the nasal cavities of flutropium was effective in experimental model of ACh and histamine-induced nasal secretion, 2) M3 cholinergic receptors may be dominant in the nasal secretion induced by ACh and 3) the experimental model of drug-induced nasal secretion in guinea pigs used in the present study can be employed to develop therapeutic drugs for nasal secretion.

Validation of guinea pig model of allergic rhinitis by oral and topical drugs

“…Different mediation mechanisms can be attributed to different symptoms in rhinitis model e.g. thromboxane A 2 and peptide leukotrienes in early and late phase nasal blockage [7], histamine H 1 receptors in sneezing and itching [8], histaminergic and cholinergic mechanisms in nasal secretion [9] and tachykinins in sneezing [10]. The molecular mechanisms in animal model of rhinitis or human rhinitis and the parallels between the two are incompletely understood, however, some symptoms of rhinitis such as sneezing, nose rubbing, nasal blockage and rhinorrhea can be modeled in experimental animals [11].…”