Effect of Nitric Oxide on the Proliferation of Cultured Human Tenon Capsule Fibroblasts Exposed to Benzalkonium Chloride

ABSTRACT

PURPOSE: To investigate whether the effect of benzalkonium chloride (BAK) on the proliferation of human Tenon capsule fibroblasts (HTCF) is mediated by nitric oxide (NO) in tissue culture . METHODS: HTCF were exposed to various concentrations of BAK for 24 hr and the cellular proliferation and production of NO were assessed by MTT and Griess assays, respectively. A non-specific nitric oxide synthase inhibitor, 0, 5 mM N(omega)-Nitro-L-arginine methyl ester (L-NAME), or NO donor, 100 micro M sodium nitroprusside (SNP), was co-administered with BAK to assess the effect of NO on the proliferation of cells. RESULTS: BAK decreased cellular proliferation in a dose-dependent manner and this effect was accompanied with decreased nitrite production. The cellular proliferation was increased significantly with BAK/SNP co-administration but decreased with BAK/L-NAME co-administration. CONCLUSIONS: NO donor increased the proliferation of HTCF which was decreased by BAK. The effect of BAK on the proliferation of HTCF may be possibly mediated by NO.