RESUMO
PURPOSE: The purpose of this study was to investigate the protective effects of sodium hyaluronate eyedrop against corneal epithelial disorders caused by antiglaucomatous eyedrops using an electrophysiological method. METHODS: Three kinds of antiglaucomatous eyedrops, including benzalkonium chloride (BAC) as an ophthalmic preservative, a BAC-free antiglaucomatous eyedrop, and a sodium hyaluronate eyedrop, were used in this study. Eyedrops were applied to excised rabbit corneas, and the electrophysiological property of the cornea was monitored using an Ussing chamber with a turnover system that mimics human tear turnover. With this system, changes in transepithelial electrical resistance (TER) in the corneal surface were recorded. RESULTS: The corneal TER after applying antiglaucomatous eyedrops tended to decrease concomitantly with increasing the concentration of the BAC included as a preservative. On the other hand, there was no significant change in the corneal TER for the initial 60 min after applying sodium hyaluronate eyedrop compared with those of the control. Moreover, the pretreatment with a sodium hyaluronate eyedrop reduced the extent of decrease in the corneal TER observed after application of antiglaucomatous eyedrops alone. CONCLUSION: Those results indicate that a sodium hyaluronate eyedrop has the potential to protect the corneal surface from antiglaucomatous eyedrops, including BAC as an ophthalmic preservative.