Ocular Defects in Newborn Rats Treated with 5-Iododeoxyuridine (IUDR)

Newborn Wistar and Sprague-Dawley rats were treated parenterally with IUDR at the rate of 400 mg/kg or 200 mg/ kg per day for 5 days beginning at 1 day of age. Treated and control animals were killed at 20 days of age and tissues processed for light and electron microscopy. In treated rats, developmental defects were observed in the eye, cerebellum, and kidney. Ocular lesions were most extensive in the retina and were characterized by disruption of the architecture and dysplastic rosette formation in the outer and inner nuclear cell layers. Although used as an antiviral substance, the ability of IUDR to induce developmental defects in the newborn rat emphasizes the need for further investigation.