Figure 5.

Changes in the reference space affect podocyte density. This illustrates one source of error in assessing glomerular podocyte number by counting the number of podocyte nuclear hits per glomerular cross section. If the glomerular volume increases, the chances of a single section intersecting a podocyte nucleus will decrease even if the total number of podocytes is unchanged. These two reference spaces (A and B) contain the same number of particles (podocyte nuclei). Because of the larger size of B, single sections through it contain fewer particle profiles per section than sections through space A. In this case, section 1 intersects 3 particles in A and 1 particle in B. Section 2 intersects 2 particles in A and 1 particle in B.