Functional Damage in the Developing Brain Induced by Maternal Environmental Agents: Ethanol, Tobacco and Low‐Copper Level

To evaluate tests for behavioral teratology in animals, brain dysfunction caused by maternal environmental agents is compared both epidemiologically and experimentally. Ethanol: The features of CNS involvement in human FAS (fetal alcohol syndrome) and FAE (fetal alcohol effects) are developmental delay and intellectual impairment. One of the most vulnerable structures in the rat fetus exposed to ethanol in utero is the synaptic formation in the hippocampus. What test for brain dysfunctions, such as deficits in learning, inhibition and attention, is there? Tobacco: Thirty‐three percent of human FTS (fetal tobacco syndrome) cases have CNS involvement, which is characterized by developmental delay, and behavioral problems such as a short attention span and hyperactivity. As to the concomitant effects of ethanol and tobacco on human offspring, CNS involvement appeared to be most specific for alcohol exposure, but was also observed slightly with smoking without drinking. How can the effects of concomitant substances be discriminated in an animal test? Low‐copper level in brain: Related to the development of their offspring, abnormal movements in brindled mutant mouse heterozygotes are observed. These findings may be influenced by both copper and oxygen radical metabolism. The teratogenic effects of triethylene tetramine dihydrochloride, a chelating drug for copper on the fetal mouse brain are noted both grossly and microscopically. How can the abnormal CNS development in relation to a certain biochemical mechanism be detected by means of an animal test? In conclusion, to examine behavioral teratology in animals, specificity and accuracy should be considered in comparison with in humans.