Effect of Nitric Oxide on the Permeability of Trabecular Meshwork Cell Monolayer

Abstract

Purpose: To investigate the effects of nitric oxide (NO) on the permeability of cultured human trabecular meshwork cell (HTMC) monolayer. Methods: HTMCs were cultured until confluency in the Transwell inner chamber and then exposed to 0, 10 or 100 μm S-nitroso-N-acetyl-DL-penicillamine (SNAP) and 0.5 mm L-N-Nitroarginine methyl ester (L-NAME) for 24 hours. Permeabilities of carboxyfluorescein through the HTMC monolayer were measured using a spectrofluorometer after 2 hours in the outer chamber. Cellular viabilities and production of NO were assessed using 3-(4, 5 –dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and Griess assay, respectively. Results: The cellular survival was not affected by 10 or 100 μm SNAP (p > 0.05) but NO production increased in a dose-dependent manner (p 0.05). Conclusions: NO increased the permeability of carboxyfluorescein through the HTMC monolayer in a dose-dependent manner. Thus, NO could increase trabecular outflow by increasing the permeability of trabecular cell layer in addition to trabeular messwork (TM) relaxation. J Korean Ophthalmol Soc 2015;56(5):771-775