Teratogenicity screening in standardized chick embryo culture: effects of dexamethasone and diphenylhydantoin.

Teratogenic and toxic effects of DXM and DPH were tested using a standardized chick embryo culture. Survival, growth and malformations were scored with respect to the drug concentrations used. DXM (greater than 10(-8) mol/l) inhibited the differentiation of the extraembryonic blood circulation and induced craniofacial anomalies. DPH (greater than 1.5 10(-5) mol/l) induced cardiomegaly, craniofacial and somitic anomalies. Both drugs were lethal at 10(-3) mol/l. Comparison of results obtained with 8 drugs shows that the method has a good discriminative power and specificity and that it can be used as a simple, reliable and economical primary screening test, making it possible to reduce the use of animals in toxicological studies.