Malondialdehyde (MDA) levels in the a) brain, b) heart, c) aorta and d) kidney tissues in chronic renal failure (CRF). Control (C), Saline (SF) treated, Captopril (CAP) treated, Valsartan (VAL) treated, N-acetyl-L-cysteine (NAC) treated, CAP+NAC treated, VAL+NAC treated CRF groups. ** p<0.01 and *** p <0.001 compared with control, + p<0.05, ++ p<0.01, +++ p<0.001 compared with SF treated CRF group, φ p<0.05 compared with CAP treated CRF group, γ p<0.05 compared with VAL treated CRF group.