小脳の生後発達に及ぼすcytosine arabinosideの影響に関する実験的研究

抄録

Suckling mice were injected subcutaneously with cytosine arabinoside (ara-C), a drug known to interfere with DNA synthesis. The animals were divided into three experimental groups. Group I received a dosage of 30 mg/kg, group 2, a dosage of 50mg/kg and group 3, a dosage of 100 mg/kg. The animals belonging to three groups were injected subcutaneously with this chemical on postnatal days 2, 3 and 4 successively. Subsequently these animals and control animals were sacrificed on postnatal days 5, 7, 15, 20 and 30, and their cerebella were examined microscopically. The results were summarized as follows. 1. On postnatal day 5, the external granular layer of treated animals was sellectively damaged and almost completly disappeared. The Purkinje cells, however, remained normal. 2. In groups 1 and 2, repair of the external granular layer was noticed on postnatal day 10 and 15, respectively. Repair of the external granular layer was prominent in the posterior lobes. 3. Sizes of cerebe lum of 30-day-old treated animals were smaller than those of age-matched controls. 4. Cytoarchitecture of cerebella of 20- and 30-day-old treated animals differed greatly from that of control. In the anterior lobes of the treated cerebellum, the Purkinje cells were dispersed throughout the molecular layer and granule cells were few in the granular layer. In the middle and posterior lobes, the Purkinje cells were arranged irregularly and granule cells were numerous in the granular layer. However, some cells were remained in the molecular layer, thus forming heterotopic granule cell mass. 5. Most animals belonging to groups 2 and 3 showed ataxic gait and tremor.