[Neuronal kinases in glial cytoplasmic inclusions in patients with multiple system atrophy]

Glial cytoplasmic inclusions (GCI) occur characteristically in the cytoplasms of oligodendrocytes of brains with multiple system atrophy. We examined whether proline-directed protein kinases, which have been found in several neuronal inclusion bodies such as neurofibrillary tangles and Lewy bodies, are associated with GCI. We unexpectedly have observed cdk 5 and MAPK in GCI. These kinases were not immunolabeled in coiled bodies which are oligodendroglial inclusion bodies in brains with progressive supsranuclear palsy and Alzheimer's disease. We also found microtubule-associated protein 2 in oligodendrocytes in brains with MSA, which have not been observed in normal controls or neurological disease controls. Cdk 5 and MAP 2 are principally neuronal proteins. MAPK have been found in neuronal somata and some astrocytes, but not in oligodendrocytes. Thus, the present results suggest that oligodendrocytes in MSA harbor an abnormal phenotypic nature in terms of the aberrant expressions of the principally neuronal proteins.