Stereological Quantitation of Leydig and Sertoli Cells in the Testis from Young and Old Men

One of the newer stereological methods, the optical fractionator, was applied to the study of the effects of ageing on the human testis. The estimated total number of Sertoli and Leydig cells per testis in men younger than 30 years were 430×10 (CV = SD/mean = 0.35) and 117×10 (CV = 0.53), respectively, while in men older than 50 years the estimated total Sertoli cell number was 266×10 (CV = 0.46) and the mean Leydig cell number 83×10 (CV = 0.53). The difference between the number of Sertoli cells in men younger than 30 years compared with men older than 50 years was close to statistical significance (p = 0.052) while no differences was found in total Leydig cell number (p = 0.22).