Comparative morphometric study of cerebellar neurons. II. Purkinje cells

The morphometric characteristics of Purkinje cell perikarya and dendritic trees were evaluated in 4 men, 4 cats and 4 rats. Purkinje cell perikaryon size, as well as the number of synapses and the synaptic surface per Purkinje cell, are significantly greater in man than in the cat and the rat. No significant differences were found as concerns the volumetric densities of nuclei and nucleoli. It is advanced that the higher number of synaptic afferences per Purkinje cell in man may represent the morphological counterpart for the increased resolution of the human mossy fiber-granule cell afferent system.