抄録
Oligodendrocytes and myelin in the corpus callosum of black tremor and normal hamsters aged 3, 7, and 14 weeks were ultrastructurally examined to determine myelination index (ratio of myelin thickness/diameter of axon), percentage of naked axons, and proportions of oligodendroglial subtypes (light, medium and dark). The mutant hamsters were remarkably hypomyelinated, with a low myelination index and a high proportion of naked axons, but the proportions of the three subtypes in the mutants were comparable with those of normal hamsters at 3 weeks of age, suggesting the low myelinogenetic activity of oligodendrocytes in the mutant. Furthermore, oligodendrocytes of the mutant hamsters appeared to mature earlier than those of age-matched controls, since the proportions of dark inactive oligodendrocytes at 7 and 14 weeks of ages were higher than those of the control hamsters.
