Figure 3.

Toluidine blue staining of semithin rat kidney sections at different stages of Thy1.1 nephritis. Capillaries of healthy glomeruli (A) assemble in a compact structure with inconspicuous mesangial region. Day 3 of nephritis (B) is characterized by the presence of first microaneurysms (black asterisk) and wide urinary space (white asterisks). At day 5 (C), enlarged capillaries (black asterisks) and microaneurysms are frequently filled with erythrocytes (Er). Starting from day 5 (C), but very pronounced by day 9 (D), is the prominent, dense mesangial region (white asterisks), which pushed the dilated capillaries to the periphery of glomerulus (black asterisks). At day 14 (E and F), intussusception (ie, pillar formation) is represented here as an insertion of tiny walls between the capillaries (arrowheads in F, which is a zoom of the area surrounded by the rectangle in E). Bc = Bauman capsule.