Contributions to the study of bisazo dye(s) induced eye anomalies in rats

Eye anomalies were studied in embryos and foetuses of pregnant Wistar albino rats injected i.p. on day 9 of pregnancy with trypan blue (8-15 mg/100 g) and Niagara sky blue 6B (10-15 mg/100 g). Specimens were obtained by killing or by repeated surgical interventions between the 12th and 20th day of pregnancy. Microscopical changes were recorded in 170 embryos and foetuses of the experimental series and in 50 control specimens. Anophthalmia nad microthalmia (of various degrees) were the main anomalies induced by both dyes used. Other anomalies, less frequent, involved the whole eye or one or more eye components. No degenerative and necrotic changes the whole eye or one or more eye components. No degenerative and necrotic changes were recorded and no features attesting the vascular origin of malformations could be found. The persistence of eye appendages even in the total absence of any eye rudiment was constantly observed. Control specimens showed no microscopical changes of the developing eye. Some problems concerning possible pathogenic pathways are discussed.