We characterized changes in the visual behavior of pigmented rat in which a loss of the retinal pigment epithelium (RPE) was experimentally induced with retro-orbital venous plexus administration of sodium iodate (NaIO3).We compared and correlated these changes with alterations in neural retinal structure and function.

RPE loss was induced in 250g pigmented rat with an retro- orbital sinus injection of 5% NaIO3 at two concentrations: 40, 60 mg/kg. At 1, 7, 14, 21, and 28 days (d) post injection (PI) a behavioral test was performed to evaluate visual function. Eye morphology was then assessed for changes in both the RPE and neural retina.

: NaIO3 induced RPE degeneration was both dose and PI time dependent. Our low dose showed effects, while our high dose caused the most damage. At 7 d PI visual behavior became abnormal and patchy RPE cell loss was observed. From7 d PI onward, changes in retinal morphology and visual behavior became more severe.

These results show that NaIO3 dosage and/or time PI can be varied to produce different, yet permanent deficits in retinal morphology and visual function