Acute stress to excised vocal fold epithelium from reactive oxygen species.

Objectives/Hypothesis: Vocal fold epithelium is exposed to reactive oxygen species from the inhaled environment and from tissue inflammation. The objective of this study was to explore the functional and structural consequences of reactive oxygen species exposure on vocal fold epithelium. Study Design: In vitro, prospective study design. Methods: Hydrogen peroxide (H₂O₂), a common reactive oxygen species, was utilized in this study. Freshly excised, viable porcine vocal fold epithelia (N = 32) were exposed to H₂O₂ or sham challenge for 2 hours. Electrophysiology, western blotting, and light microscopy were used to quantify the functional and structural effects of reactive oxygen species on vocal fold epithelia. Results: Exposure to reactive oxygen species did not significantly alter transepithelial resistance. There was a small, nonsignificant trend for decreased concentration of epithelial junctional complex protein with reactive oxygen species challenge. Minimal changes to the gross structural appearance of vocal fold epithelia were also noted. Conclusions: The stratified squamous epithelia of the vocal folds effectively defend against an acute reactive oxygen species challenge. The current study lays the groundwork for future investigations on the effects of reactive oxygen species on vocal fold epithelia that are compromised from phonotrauma. [ABSTRACT FROM AUTHOR]