Focal cerebellar dystrophy caused by transplacental administration of methylnitrosourea

Methylnitrosourea (MNU), 20 mg/kg, was given IP to CD-1 mic on day 16 of pregnancy and the offspring examined at 3 and 5 weeks of age. In addition to a general reduction in brain size in all specimens, there were focal alterations in cerebellar architecture. Specifically, the granule cells of the anterior lobe and vermis were reduced in number and ectopic in localization. There were concomitant changes in the localization of the Purkinje cells suggesting changes in migration influences. These experiments used a short-lived (15 minute), direct-acting DNA alkylating agent to produce focal cerebellar damage. MNU therefore, appears to be a promising tool for examining regional developmental abnormalities in the central nervous system.