[Development of an experimental rabbit model of rhinitis medicamentosa].

Abstract

Background: Rhinitis medicamentosa (RM), resulting from prolonged use of nasal decongestants, represents a significant clinical problem. The pathogenetic mechanisms of RM remain insufficiently studied, and existing methods for assessing the state of the nasal mucosa require improvement. The development of an experimental model of RM is necessary for testing new therapeutic approaches.

Objective: To develop an experimental model of RM in rabbits, evaluate morphological changes in the nasal mucosa, and test the photoplethysmography method for non-invasive diagnosis of microcirculatory disorders.

Material and methods: The study was conducted on 18 Soviet Chinchilla rabbits. The RM model was induced by intranasal administration of 0.1% xylometazoline solution (200 μl/nostril, 2 times/day, 14 days). The control group received saline. Histological analysis of the mucosa was performed on days 8 and 15. The state of microcirculation was assessed by photoplethysmography using a cold test. Data registration was carried out in vivo with subsequent digital signal processing.

Results: Progressive histological changes were revealed: epithelial dystrophy, a decrease in the number of goblet cells, and vascular alterations. The photoplethysmography demonstrated a significant decrease in the ratio of photoplethysmogram amplitudes in the RM group (median 0.76 vs. 1.48 in the control; p<0.01), reflecting impaired microcirculation.

Conclusion: An experimental model of RM in rabbits was developed, confirmed by histological and photoplethysmographic data. The photoplethysmography showed high sensitivity for non-invasive assessment of the mucosal state, opening up prospects for its application in clinical practice and further studies of RM therapy.