Ultrasonographic Evaluation of the Kidney in 5/6 Nephrectomized Rats: Correlation with Biochemical and Histopathological Findings

Aim: To characterize the kidney alterations associated with renal mass reduction by two-dimensional ultrasound and assess the correlation of the ultrasonographic parameters with the histological and biochemical findings. Materials and Methods: Rats were divided into two groups: sham-operated animals (n=13), and animals which underwent renal mass reduction (RMR) through 5/6 nephrectomy (n=14). Renal length, renal thickness, cortical thickness, medullary length and echogenicity of the kidneys were evaluated by ultrasonography at 3 and 6 months after the RMR. Results: Except for the renal length, the renal dimensions at 3 and 6 months were significantly higher in the RMR group when compared to the sham-operated group (p<0.05). Furthermore, the cortical and medullary echogenicity was significantly higher in the RMR group when compared to the sham-operated group (p<0.05). A significant correlation was observed between the plasma creatinine level and the renal length 3 months after RMR (r=-0.612, p=0.045). Conclusion: These data support future application of ultrasonography for monitoring the progression of renal damage in chronic studies with the 5/6 nephrectomy model.