Ascorbic Acid Enhances Nitric Oxide Production in Trabecular Meshwork Cells

Purpose: This study investigated the role of ascorbic acid on the production of nitric oxide (NO) in the trabecular meshwork (TM) cells. Methods: After primarily cultured human TM cells were exposed to 1, 10, and 100 μM of L-ascorbic acid(LAA), with or without co-administration of 1 mM sodium nitroprusside or 100 μM hydrogen peroxide for 48 hr, cellular survival and NO production were measured with MTT and Griess assay, respectively. Results: LAA significantly potentiated NO production in a dose-dependent manner (p<0.05) without affecting cell viability. LAA increased cell viability after hydrogen peroxide-induced oxidative stress in a dosedependent manner. LAA enhanced NO production in TM cells and showed a cytoprotective effect against hydrogen peroxide-induced oxidative stress. Conclusions: LAA might be involved in the regulation of trabecular outflow by enhancing NO production in TM cells. Korean Journal of Ophthalmology 19(3):227-232, 2005