Abstract
In this study the total number of nuclei of the adenohypophysial cells in rats was counted by using the integral serial sections. If each section is 5μ in thickness, the population is subject to be overestimated approximately three times of the true number of nuclei, because a section contains not only the entire nuclei but also some nuclear fragments. For this reason, a compensation is required to correct the measured number of nuclei. Initially, the method to calculate the mean radius of nuclei from the measured value of radii of nuclei including fragments was described, then the following formulae which correct the overestimation were ellicited:
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Where mi is the total number of nuclei including the alienated fragments which appear in the i-th section; 2r represents the average diameter of nuclei in the horizontal direction (μ) 2a does the thickness of sections (μ) M and A are the real number of nuclei in the adenophyophysis. On the occasion when there is no remarkable difference between 2a and r, and when the first and last sections contain no centers of nuclei, the first formula is applicable. When 2a is large enough to contain the centers of nuclei in the first and last section, the second formula is applicable. The number of nuclei of rat's pituitaries measured by the present method was compared with that by the other methods. This comparison suggested the validity of the present formulae.
