Objective: We aimed to assess the effects of electronic nicotine delivery system (ENDS) or also termed electronic cigarette vapor on the laryngeal mucosa of rats.
Materials and methods: Sixteen female Wistar albino rats were divided into two groups. The study group was exposed to ENDS vapor for 1 hour/day for 4 weeks. The control group was not subjected to any chemical or physical stimulus. The vocal folds of the study and control group rats were evaluated histopathologically by hematoxylin and eosin staining and immunohistochemically by Ki67 staining. Epithelial distribution, inflammation, hyperplasia, and metaplasia were evaluated.
Results: Epithelial distribution and inflammation did not differ between the two groups. Two cases of hyperplasia were detected in the study group but there was no hyperplasia in the control group. Four cases of metaplasia were detected in the study group and one case in the control group. Statistical analysis revealed no significant difference between the study and control groups (P = 0.131 and 0.106, respectively).
Conclusions: Exposure to ENDS for 4 weeks caused hyperplasia and metaplasia of the laryngeal mucosa of rats but this was not significant statistically. These results implemented that further studies with larger cohort and longer duration are required to evaluate long-term effects.
Keywords: Electronic cigarette; Electronic nicotine delivery system; Histopathology; Larynx; Metaplasia.
Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.