title: Effects of Electronic Nicotine Delivery System on Larynx: Experimental Study.
abstract: 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.
  
  
  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.
authors.affiliation: Okmeydanı Training and Research Hospital, ENT Clinic, Istanbul, Turkey. Electronic address: ziyasalturk@gmail.com.
authors.forename: Ziya
authors.initials: Z
authors.lastname: Salturk
authors.affiliation: Okmeydanı Training and Research Hospital, Pathology Clinic, Istanbul, Turkey.
authors.forename: Çağlar
authors.initials: Ç
authors.lastname: Çakır
authors.affiliation: Okmeydanı Training and Research Hospital, ENT Clinic, Istanbul, Turkey.
authors.forename: Gürcan
authors.initials: G
authors.lastname: Sünnetçi
authors.affiliation: Okmeydanı Training and Research Hospital, ENT Clinic, Istanbul, Turkey.
authors.forename: Yavuz
authors.initials: Y
authors.lastname: Atar
authors.affiliation: Okmeydanı Training and Research Hospital, ENT Clinic, Istanbul, Turkey.
authors.forename: Tolgar Lütfi
authors.initials: TL
authors.lastname: Kumral
authors.affiliation: Okmeydanı Training and Research Hospital, ENT Clinic, Istanbul, Turkey.
authors.forename: Güven
authors.initials: G
authors.lastname: Yıldırım
authors.affiliation: Okmeydanı Training and Research Hospital, ENT Clinic, Istanbul, Turkey.
authors.forename: Güler
authors.initials: G
authors.lastname: Berkiten
authors.affiliation: Okmeydanı Training and Research Hospital, ENT Clinic, Istanbul, Turkey.
authors.forename: Yavuz
authors.initials: Y
authors.lastname: Uyar
mesh_terms: D000280:Administration, Inhalation; D000818:Animals; D066300:Electronic Nicotine Delivery Systems; D005260:Female; D006965:Hyperplasia; D007820:Laryngeal Mucosa / Q000187:drug effects* / Q000473:pathology; D008679:Metaplasia; D023421:Models, Animal; D009538:Nicotine / Q000008:administration & dosage* / Q000633:toxicity; D018722:Nicotinic Agonists / Q000008:administration & dosage* / Q000633:toxicity; D017208:Rats, Wistar; D018570:Risk Assessment; D013997:Time Factors; D014827:Vocal Cords / Q000187:drug effects* / Q000473:pathology
chemical_list: D018722:Nicotinic Agonists; D009538:Nicotine
keywords: Electronic cigarette; Electronic nicotine delivery system; Histopathology; Larynx; Metaplasia