F Benencia1, M C Courrèges, G Gamba, H Cavalieri, E J Massouh. 1. Laboratory of Immunochemistry, Department of Biological Chemistry, Faculty of Sciences, University of Buenos Aires, Pabellón II, Piso 4, Ciudad Universitaria, 1428 Buenos Aires, Argentina. fbenen@qb.fcen.uba.ar
Abstract
PURPOSE: To study the effect of aminoguanidine (AMG), an inhibitor of nitric oxide production, on the ocular infection of Balb/c mice with herpes simplex virus (HSV) type 1 strain F and HSV-2 strain G. METHODS: Animals were treated with different amounts of AMG (0.5, 0.1, and 0.05 mg/mouse) by topical application in the eye from postinfection (PI) days -2 through +5, considering 0 the day of infection. At different PI days, development of herpetic keratitis was evaluated in treated and control mice. RESULTS: Treated animals showed a dose-dependent increase in ocular disease after viral infection, compared with control animals. Viral titers in ocular washings were higher in AMG-treated mice (PI day 2, HSV-1: AMG 0.5 mg, 1.3 x 10(3) plaque-forming units (PFU)/ml; control, 0. 22 x 10(2) PFU/ml, P < 0.025). At PI day 3, control corneas had only scattered inflammatory cells, whereas those from treated animals showed a conspicuous infiltrate consisting primarily of neutrophils. Viral titers were also higher in brains of treated mice. These animals died earlier and in a greater proportion than control animals (percentage of mortality, PI day 12, HSV-1: AMG 0.5 mg, 40% +/- 4%; control, 18% +/- 3%, P < 0.05). CONCLUSIONS: These data indicate an inhibitory effect of nitric oxide on HSV ocular infection.
PURPOSE: To study the effect of aminoguanidine (AMG), an inhibitor of nitric oxide production, on the ocular infection of Balb/c mice with herpes simplex virus (HSV) type 1 strain F and HSV-2 strain G. METHODS: Animals were treated with different amounts of AMG (0.5, 0.1, and 0.05 mg/mouse) by topical application in the eye from postinfection (PI) days -2 through +5, considering 0 the day of infection. At different PI days, development of herpetic keratitis was evaluated in treated and control mice. RESULTS: Treated animals showed a dose-dependent increase in ocular disease after viral infection, compared with control animals. Viral titers in ocular washings were higher in AMG-treated mice (PI day 2, HSV-1: AMG 0.5 mg, 1.3 x 10(3) plaque-forming units (PFU)/ml; control, 0. 22 x 10(2) PFU/ml, P < 0.025). At PI day 3, control corneas had only scattered inflammatory cells, whereas those from treated animals showed a conspicuous infiltrate consisting primarily of neutrophils. Viral titers were also higher in brains of treated mice. These animals died earlier and in a greater proportion than control animals (percentage of mortality, PI day 12, HSV-1: AMG 0.5 mg, 40% +/- 4%; control, 18% +/- 3%, P < 0.05). CONCLUSIONS: These data indicate an inhibitory effect of nitric oxide on HSV ocular infection.