Purpose: The aim of this study was to evaluate the efficacy of hammerhead ribozyme to the
proliferating cell nuclear antigen (PCNA-Rz) and 5-fluorouracil (5-FU) in experimental
choroidal neovascularization (CNV) model in rats.
Methods: Laser was used to induce CNV in each eye of 44 rats. For angiography studies, injections of either a mixture of PCNA-Rz 10 µg/µL and 5-FU 1.5 µg/µL, versus the same dose of either drug alone versus a control injection of Hanks' Balanced Salt Solution (HBSS) were performed. We also studied this regimen to evaluate scar size and volume.
Results: There was significantly less angiographic leakage for the treated eyes compared to
the controls by 3.53 grading points (P = 0.0005); CNV leakage was reduced in the combination
group compared to 5-FU alone by 1.75 grading units (P = 0.04) and compared to PCNARz
by 2.22 grading units (P = 0.07). The scar size and volume were smaller (diameter 354.6 ±
174.2 µm vs 477.3 ± 157.0 µm), (thickness 52.7 ± 43.0 µm versus 79.6 ± 46.2 µm) with a reduction
in scar volume of 44.8%.
Conclusions: Subretinal injection of PCNA-Rz and 5-FU mixture is more effective as treatment
of laser-induced CNV, than either drug alone. The majority of the antiangiogenic effect
is a result of 5-FU activity with a contribution by the PCNA ribozyme.
