Purkinje cell number and size, comparison of human and rat cerebella

Estimates of total number and mean volume of Purkinje cells in five human and nine rat cerebella were obtained using stereological methods based on unbiased principles and estimators. The average total number of Purkinje cells was 30.5 106 (CV = SD/mean = 0.13) in humans and 0.61 106 (CV = 0.21) in rats. Thus the total number of Purkinje cells was 50 times higher in the human compared with rats, while numerical density per mm3 was 13 times lower in humans (0.81 103) compared with rats (10.1 103). The nucleator was applied to estimate the number weighted mean volume of the large and unevenly distributed Purkinje cells. In humans the mean volume of Purkinje cell perikaryon is 14,250 μm3 (CV = 23%). The data are compared with the mean Purkinje cell perikaryon volume in rats, 5,300 μm3, with a CV of 5%. Expectedly, the variation in Purkinje perikaryon volume between individuals are larger in humans than the individual variation between rats.