An early cytoplasmic change before Lewy body maturation: an ultrastructural study of the substantia nigra from an autopsy case of juvenile parkinsonism.

Neurons containing a central pale area which may possibly represent an early cytoplasmic change before Lewy body maturation were observed in the substantia nigra from a rare autopsy case of juvenile parkinsonism. Ultrastructurally, such neurons exhibited cytoplasmic swelling along with disappearance of the rough endoplasmic reticulum from the central part of the perikaryon. The pale central cytoplasm was replaced by numerous-cored vesicles, mitochondria, ribosome-like granules and a few Lewy body filaments. The relation of this central pale area to the pale body is discussed.