Olfactory mucosal microstructural changes in a rat model of acute rhinosinusitis with dysosmia

Abstract

ABSTRACT. This study aimed to examine olfactory mucosal changes in a rat model of acute rhinosinusitis and to determine how acute rhinosinusitis induces dysosmia. Total 100 rats were divided into the experimental (N = 80) and control (N = 20) groups. An acute rhinosinusitis model was established in the experimental rats. From the experimental group, 20 rats each were sacrificed at 1, 2, 3, or 4 weeks. The control group was sacrificed at 1 week without inoculation. Olfaction was tested by the buried food pellet test before killing the rats, and the duration until the pellet was recorded and analyzed by a statistical software program. Mature olfactory receptor neurons (ORNs) and olfactory ensheathing cells (OECs) were examined. The durations spent by the experimental group in the BFPT were 402.9 ± 9.3, 453.7 ± 7.3, 351.9 ± 8.9, and 278.7 ± 8.1 s at 1, 2, 3, and 4 weeks, respectively. These durations were greater than that of the control group (178.3 ± 6.6 s), and the difference was statistically significant (P < 0.01). A reduction in ORNs and thinning of the epithelium were detected in the experimental group, most notably in the 2nd week and less in the fourth week. OECs were reduced in the 1st week, increased in the 2nd week, and almost completely recovered in the fourth week. In addition, some growing OECs were detected in the experimental group. Acute rhinosinusitis decreased both the mature ORNs and OECs, but OECs increased faster than the ORNs.

Morphological evaluation using MRI of the olfactory filaments (fila) in a post‐traumatic olfactory rat model

“…BFPT has been widely employed to assess the olfactory function of rats. 40 , 48 Another interesting finding of our study is that the blunted needle surgery did not impair the OF. This finding differs from that of some reports that use similar method to damage the OFs.…”

“…The latency to find the food (forelimbs clinging to the food pellet or gripping it with teeth) after introduction into the test situation was recorded. 40 If the rat did not find the food pellet within 5 min, the latency was recorded as 300 s. The average latencies for each of 5 days of testing was used for analysis.…”

Protective Effects of Melatonin and Selenium against Apoptosis of Olfactory Sensory Neurons: A Rat Model Study

“…As described previously, acute rhinosinusitis was induced bilaterally in 24 animals. 12,13 After skin incision, the superior parts of the maxillary sinuses were visualized. Type 1 Streptococcus pneumoniae solution, 1 mL, which consisted of 10 7 -10 9 pneumococci/mL, was inoculated into the maxillary sinuses bilaterally; then, an 2 × 3 × 15-mm Merocel stick (Medtronic Xomed.…”