Compensatory hypertrophy of the kidney

Abstract

The stimulus to compensatory hypertrophy was given by the removal of one kidney from a rat. The degree of hypertrophy was measured by comparing the weight of the remaining kidney forty days after the operation with the weight of the kidney of rats in which one kidney had been exposed but not removed. This value is expressed as a percentage. Thus if the weight of one kidney of the control rat was 1000 mg. and the weight of the remaining kidney in the nephrectomised rat was 1300 mg., the degree of compensatory hypertrophy was 30 per cent. The percentages given are the averages of groups of rats. It was intended that there should be 25 rats in each group, but since all of the animals did not become pregnant at the expected time this number was not reached in all of the experiments. The diet used was adequate for growth and for reproduction and contained 17.8 per cent of protein, 24.9 per cent of fat, and 42.2 per cent of carbohydrate. The amount of food taken was nearly the same in all experiments except in the lactation experiment. In this instance the caloric intake rose from 25 calories to 90 calories per 100 grams of body weight per day.