Comparison of compensatory hypertrophy of the kidney after unilateral nephrectomy on adult and senile rats

Abstract

One kidney was removed from rats weighing 35–900 g. The animals were killed 2, 14, 30, and 60 days after the operation. The degree of compensatory hypertrophy of the remaining kidney varied considerably in the animals of different ages, although it was not reduced in old age. The weight of the hypertrophied kidney of the old rats 60 days after the operation was 55–92% of the combined weight of both kidneys in the control. Hypertrophy of the kidney at all ages was accompanied by increased proliferation of cells of the tubules, especially the proximal tubules. An increase in the size of the renal corpuscles during hypertrophy of the kidney was characteristic of rats of both age groups. However, with an increase in age this process developed faster and was more pronounced. At all times of investigation the hypertrophied kidney of rats of both ages contained 1. 5–2 times more “open” renal glomeruli than the kidney of the intact animal.