ABSTRACT
OBJECTIVE: The aim of this study was to investigate the association between laryngeal expression of claudin-3 and laryngopharyngeal reflux (LPR) in a rat reflux model. METHODS: Eight Wistar rats were divided into two groups. Four rats underwent total esophageal myectomy to induce reflux, and the remainder underwent a sham operation as a control. All animals were sacrificed 12 weeks after surgery to perform tissue histology and Western blot analysis. RESULTS: Lymphocyte infiltration increased significantly in the study group in both esophageal and laryngeal samples (P=0.001, 0.002, respectively). Both esophageal and laryngeal expressions of claudin-3 were significantly lower in the study group when compared with that in the control group (P=0.045, 0.037, respectively). CONCLUSION: The results of this study suggest that a decrease in claudin-3 could be a sensitive indicator of reflux laryngitis in rats.
Subject(s)
Claudin-3/metabolism , Esophagitis/metabolism , Esophagus/metabolism , Laryngitis/metabolism , Laryngopharyngeal Reflux/metabolism , Larynx/metabolism , Animals , Blotting, Western , Disease Models, Animal , Esophagitis/etiology , Esophagitis/pathology , Esophagus/pathology , Gastroesophageal Reflux/complications , Gastroesophageal Reflux/metabolism , Gastroesophageal Reflux/pathology , Laryngitis/etiology , Laryngitis/pathology , Laryngopharyngeal Reflux/complications , Laryngopharyngeal Reflux/pathology , Larynx/pathology , Rats , Rats, WistarABSTRACT
The aim of the present study was to assess the ototoxicity of kanamycin sulfate (KM) in adult rats and its underlying mechanism. Forty male Sprague-Dawley rats (6-7 weeks old) were randomly divided into the experimental group and the control group. The animals in the experimental group were injected subcutaneously with KM (500 mg/kg per day) for two weeks, and the control group received equal volume of normal saline. To assess the ototoxicity of KM, the auditory brainstem response (ABR) was recorded to monitor the changes in hearing thresholds, and the density of spiral ganglion cells (SGCs) and morphology of cochlea were observed using surface preparations and frozen sections of cochlea. The results showed that the hearing threshold of rats in the experimental group was elevated by more than 60 dB across all the frequencies two weeks after the first administration of KM. And in the experimental group, the density of SGCs became lower, and organ of Corti suffered loss of hair cells. The loss of outer hair cells (OHCs) was more severe than that of inner hair cells (IHCs), correlated with the density decrease of SGCs. We conclude that the ototoxicity of KM in the adult rats was apparent and the underlying mechanism is associated with the loss of SGCs and hair cells.
