Effects of vincristine on developing hamster embryos.

Using dosages and a route of administration which resembled those used clinically in humans, the effects of vincristine on developing hamster embryos were evaluated. The results showed that the drug exerted a highly toxic effect in a dose-dependent manner; however, it exhibited only a sporadic teratogenic (gross malformation) effect. The data on DNA synthesis indicated involvement of internal organs and structures, which needs to be verified. Overall, the teratogenicity of the drug was more pronounced during pre-organogenesis than during the organogenesis period. It was suggested that, in contrast to the data reported in the literature, the different biological response to vincristine in hamster may relate to the use of the dose-route combination, and is potentially relevant to developmental and transplacental carcinogenesis studies.