Striosomal arrangement of met-enkephalin and substance P expression in parkinsonism-dementia complex on Guam.

This report concerns a topographic immunohistochemical analysis of Met-enkephalin (MEnk) and substance P (SP) expression in the striatum from seven patients with parkinsonism-dementia complex on Guam (PDC). The striatum of seven neurologically normal subjects served as controls. MEnk-positive striosomes were readily visualized in both the caudate nucleus and the putamen of the PDC cases. Although the immunoreactivity was less than that of MEnk, SP-positive patches were detected in the PDC striatum. The patches were similar to those seen in the normal controls. These results provide additional evidence that the striatum and its efferent system appear to be preserved in patients with PDC.