Three-quarters nephrectomy in rats as a model of early renal failure.

To produce a compatible model of early renal failure easily, we prepared three-quarters nephrectomized animal. 20 Sprague-Dawley rats were divided into the following two groups: 10 rats which received three-quarters nephrectomy (Nx group), assuming the weight of both kidneys to be equal, and another 10 rats which underwent sham operations (S group). The levels of creatinine clearance in Nx group and S group were 286.5 +/- 33.5 vs. 431.1 +/- 55.9 microliters/min/100 g BW (P less than 0.001) on week 2, and 233.0 +/- 16.7 vs. 562.3 +/- 62.9 microliters/min/100 g BW (P less than 0.001) on week 10, respectively. The indirect and direct systolic blood pressure (SBP) values of Nx group and S group at the 10th week were 154.5 +/- 5.5 vs. 131.1 +/- 3.6 mmHg (P less than 0.01), and 148.2 +/- 4.8 vs. 130.7 +/- 6.6 mmHg (P less than 0.01), respectively. Significant changes in the levels of urinary protein excretion, urinary sodium output, urinary epinephrine, urinary norepinephrine and plasma renin activity between both groups were recognized on the 10th week. The planar area of Nx group was significantly increased as compared to that of S group (11.0 +/- 0.3 vs. 7.2 +/- 0.1 x 10(-3) mm2, P less than 0.001). It is concluded that this model resembles early renal failure in humans because slow progression of renal dysfunction occurred with mild elevation of SBP, and that it is adequate for evaluating the influence of glomerular hypertrophy, resulting in glomerulosclerosis.