Cerebellar dysgenesis in rats by diaplacental effects of 7,12-dimethylbenz[a]anthracene

7,12-Dimethylbenz[a]anthracene (DMBA) administered iv to pregnant Sparague-Dawley rats produced cerebellar malfunction in at least 10% of the offspring. The underlying morphologic basis of the cerebellar symptomatology was found in maldevelopment of cerebellar cortex, ranging from focal loss of granule and Purkinje's cell layers to extensive areas of cortical disorganization with losses of granule neurons. An interference with the proliferation of the granule cell-layer primordium was suggested as a mechanism of this cerebellar dysgenesis. After a 200-day observation, no tumors were found in the offspring of the DMBA-treated, pregnant rats.