Effect of chloroquine on experimental melanin-protein-induced uveitis in Lewis rats

Purpose: To evaluate the effect of chloroquine on experimental recurrent au toimmune melanin-protein-induced uveitis in Lewis rats. Methods: Five Lewis rats were immunized with melanin to induce uveitis (group I); another six were immunized and treated with 5 mg/kg/day of chloroquine (group II). To r einduce uveitis, they received two booster injections of melanin. They were killed when uveitis was present after the last booster injection; every ey e was evaluated by means of clinical and histopathological examination. A c ontrol group of four rats received the same chloroquine dose to evaluate re tinal toxicity (group III). Results: Rats in group I showed more severe uve itis episodes than rats in group II. The second uveitis episode was more se vere in group I than in group I. Rats in group III showed no clinical or hi stopathological abnormalities. Conclusions: Chloroquine decreased the sever ity and duration of uveitis, and in two rats it prevented recurrences. Thus , chloroquine can be considered an effective treatment for chronic, recurre nt experimental uveitis.