Comparative investigations on the cataractogenic effect of a triazin-derivative in albino and pigmented rats: II. Effects documented by Scheimpflug photography.

Abstract

A Triazin-derivative from a group of industrial chemicals was found to cause cataracts in albino rats during a subchronic toxicity study. To get more insight into this effect, a study was designed with 20 albino (Wistar) and 40 pigmented (black-hooded FB 30) rats using different dosages of the test compound. In a 3 months study period, all rats were photographed with a Scheimpflug camera TOPCON SL-45 3 times, at a baseline examination, prior to any treatment, in the middle and at the end of the study period, prior to sacrifice. The black-and-white film (Kodak T-Max 400R) was standardly developed and evaluated with a Joyce-Loebl microdensitometer in 3 regions of the lens, the capsule, the cortex and the nucleus. The density data from the second and third examination clearly demonstrate that cataract development in the albino rats takes place in the cortical region, whereas in the pigmented rats it takes place in the cortical and partly in the nuclear region. In addition, one albino and two pigmented animals of the groups investigated developed bilateral mature cataracts. Differences in cataract morphology between albino and pigmented rats are presented by Eiben and Wegener (1). The results underline the importance of toxicity testings in pigmented rats, they evidence that the data derived solely from albino animals can be misleading.