Morphological changes in the cerebellar cortex of aging Macaca nemestrina.

The cerebellar cortices in 4, 10 and 20 year of Macaca nemestrina have been examined for the number of Purkinje (P) and granule cells and the deposition of lipofuscin in P cells in relation to aging. Lipofuscin distribution significantly increased with in the P cells in these animals. The number of P cells was significantly reduced, while there were no changes in the number of granule cells. It appears from this and other studies that the Purkinje cells are more prone to aging changes than the granule cells of the cerebellum both in lipofuscin formation and cell loss. Although the precise functional significance of these changes in P cells is not clear, their vulnerability may be related to changes in motor function in old age.