Morphological changes of astroglia in the cerebellar cortex of developing mice after neonatal administration of cytosine arabinoside.

Neonatal administration of cytosine arabinoside (Ara-C) induced marked hypoplasia of the mouse cerebellum. In 17-20-day-old mice with neonatal Ara-C injections, the external granular layer was still preserved as an irregular cell laminae in the superficial part of the cerebellum, in contrast to its complete disappearance in normal animals at these stages. Immunohistochemical examination using anti-glial fibrillary acidic protein and monoclonal antibody-1D11 (Ono et al: Dev. Brain Res., 50:154-159, 1989) demonstrated malformation of a palisade-like arrangement of labeled glial fibers in the superficial part of the Ara-C treated mouse cerebellum. Furthermore, the immunoreactive astroglia were observed just beneath the pial membrane and their processes were oriented to the deeper part of the molecular layer.