A Model of Allergic Nasal Congestion in Dogs Sensitized to Ragweed

Abstract

Background Acoustic rhinometry is a noninvasive method that uses sound waves to measure dimensions of the nasal cavity. Methods In this study, nasal patency was measured by acoustic rhinometry in allergic Beagle dogs sensitized to ragweed allergen. Ragweed (0.03–0.3%) or vehicle were administered intranasally in isoflurane-anesthetized dogs. Results The instillation of ragweed caused a dose-related decrease in nasal cavity volume and minimal cross-sectional area (Amin) without adverse systemic effects. Nasal cavity volume and Amin decreased within 30 minutes after instillation of the highest ragweed dose by 35.1 ± 6.0% and 66.4 ± 13.8%, respectively, and persisted for at least 90 minutes. Oral administration of α-adrenergic agonist, d-pseudoephedrine (3 mg/kg), or histamine H1 antagonist chlorpheniramine (10 mg/kg) blocked the ragweed-induced nasal congestion. Conclusion These results suggest that the canine model may be used to study upper-airway diseases such as allergic rhinitis and to evaluate the pharmacologic activity of nasal decongestants.