THE PURKINJE-CELL IN OLIVOPONTOCEREBELLAR ATROPHY - A GOLGI AND IMMUNOCYTOCHEMICAL STUDY

Purkinje cells were examined in three familial cases of olivopontocere bellar atrophy (OPCA) by means of the Golgi method, and neurofilament and calcium-binding protein immunocytochemistry. Reduced dendritic arb orizations, as seen with different techniques, early formation of axon al spheroids, and abnormal accumulation of phosphorylated neurofilamen t epitopes in dendrites, somata and axonal spheroids, together with li mited formation of proximal spine-like protrusions were the main chang es in Purkinje cells. These lesions are unlikely to be the consequence of anterograde degeneration secondary to olivary atrophy, as postulat ed by some investigators, but probably represent primary damage to Pur kinje cells in patients with OPCA. Reduced dendritic arborizations res ult in a decrease of receptor sites for parallel fibres and deprive gr anule cells of their main targets. Abnormal accumulation of neurofilam ents in somata, dendrites and axonal spheroids may contribute to an ab normal transport and may impair protein turnover in the distal regions of Purkinje cells.