Figure 7.

Detection of scattered vimentin- and CD44-positive tubular cells in the unilateral ureteral obstruction model (UUO). (A) Vimentin expression in the contralateral control kidney. Vimentin is exclusively expressed in the peritubular capillaries (10× magnification). (B – D) In kidneys that underwent UUO, de novo expression of vimentin was observed in proximal tubular cells. The cells were frequently scattered single cells or small groups of cells (arrows). Also in the interstitium, the expression of vimentin was increased (D, arrow with tail). (B) 20×, (C) 10×, and (D) 20× magnification. (E) Higher magnification (60×) of a proximal tubule showing scattered vimentin-positive cells with an undeveloped brush border (arrows) juxtaposed to differentiated proximal tubular cells with a normal brush border (arrows with tail). (F) Quantitative analysis of the number of vimentin-positive tubular cells per microscopic field (20× magnification) in the contralateral and UUO kidneys of 7-week-old rats and in the kidneys of aged 34-week-old rats. (G – I) CD44/PAS co-staining shows single or small groups of CD44-positive tubular cells with an undeveloped brush border (arrows) juxtaposed to differentiated proximal tubular cells with a normal brush border (arrows with tail) (60× magnification).