Figure 1: Density of S-phase fusiform interstitial cells evidenced by BrdU incorporation in cortex and outer medulla (OSOM, ISOM) of kidneys from control animals (Ctrl) or from animals sacrificed at increasing times (hours or days) after reperfusion. BrdU was administered to experimental animals 1 hour before sacrifice. Each column corresponds to the mean number of labeled nuclei per m m 2 ( ± S D ) determined after examination of each region of the kidney for each experimental group ( 𝑛 = 4 ) ( 𝑃 < . 0 1 versus control).