Effects of VOO on collagen distribution in rats with sub-chronic EP a) Renal tissue of groups II and I with normal distribution of collagen Renal tissue of group III with increased distribution of collagen Renal tissue of group IV with nearly normal distribution of collagen Masson's trichrome staining ( × 100). b) Effects of VOO on grade of interstitial fibrosis in rats with sub-chronic aP˂0.05 compared to group I, bP˂0.05 compared to group II, cP˂0.05 compared to group III I: control group, II:VOO group, III: EP treated group, IV: VOO pretreatment and EP treated group (G) Renal glomeruli, (bc) Glomerular capsule, (cp) capsular space, (P) proximal convoluted tubules, (D) distal convoluted tubules, (g) Atrophied glomeruli, (h) Intertubular hemorrhage, (v) vaculles, (h) hemorrhage, (t) Tubular necrosis, (f) Fibrosis.