Drug-induced Retinal Degeneration in Rats used for Subacute Toxicity Study at the Recovery Group

Abstract

Drug-induced retinal degeneration was found in rats used for a subacute toxicity study. Light microscopically, there were folds or rosette formation in the outer and inner granular layer, edema of the layer of rods and cones, deposition of basophilic materials in the cavum subretina, swelling, degeneration and proliferation of the pigment cells, transmigration of the pigment cells and macrophages into the retina, and inflammatory cell infiltration in the chorioidea. Electron microscopically, there was accumulation of needle crystalloid substance in the swollen pigment cells, and electrondense materials in the pigment cell layer which were assumed to be debris of the outer segment.

The changes were found in rats kept for 28 days without the drug, an amphyphilic cationic compound, after completion of 28 days of treatment. But animals killed at the end of drug treatment for 28 days showed only slight swelling of the pigment cells.