Quantitative age-related changes on nuclear invaginations of neocerebellar Purkinje cells

: The aim of this study was to provide stereological data for seeking whether Purkinje neurones increase their nuclear envelope invaginations with age. The nuclear parameters considered were: ratio of absolute surface area to volume, surface density and absolute surface area. The first two parameters did not significantly change, but the absolute surface area exhibited marked variations. Regression studies showed no significant linear correlations between any of the parameters and age; so, the increase in number and/or in depth of the invaginations was not suggested. The association of invaginations with a nuclear cap of Nissl substance is a constant feature, stressing that the physiological importance of the complex is maintained throughout the ageing process.