Abstract
Abstract: :
Purpose: Time-course of Experimental Choroidal Neovascularization (CNV) in the rabbit was evaluated clinically and pathologically for the purposes of studying the pathogenesis of CNV and of exploring the suitability of this rabbit CNV model for assessing anti-angiogenic agents. Method: Rabbit CNV was induced by subretinal injection of a cocktail containing endotoxin and/or growth factor(s) with/without heparin-sepharose. The growth of CNV lesions was visualized by fluorescein angiography and quantitated by image analysis. The time course of CNV growth was studied clinically and pathologically, with some lesions followed up to one year. The suitability of this rabbit CNV model for assessing anti-angiogenic agents was appraised by the systemic administration of dexamethasone. Results: The growth of subretinal new blood vessels can be clearly observed by fluorescein angiography in 100% of the treated eyes by two weeks after injection of the endotoxin/growth factor cocktail. By week four, the size of the CNV area was twice that seen at two weeks. The size of the CNV lesion becomes relatively stable by three months after angiogenic challenge, however, the CNV lesions still demonstrate leakage by fluorescein angiography throughout the entire observation period. In addition, we report that the formation and growth of subretinal CNV in this model can be significantly inhibited by dexamethasone. Conclusion: Utilizing subretinal injection of endotoxin and growth factor(s), a reproducible and quantitative model of rabbit CNV has been demonstrated. Furthermore, the inhibition observed with dexamethasone points to the possibility of being able to evaluate effective means of pharmacological intervention.
Keywords: 308 age-related macular degeneration • 316 animal model • 514 pharmacology