UREA TOLERANCE AFTER UNILATERAL NEPHRECTOMY IN RABBITS.

The method of study has an objective somewhat different from, and lacking the precision of, the ratio of Addis and the urea clearance of Van Slyke. It serves, however, to demonstrate that although for a month after unilateral nephrectomy the remaining kidney shows diminished capacity to hold blood urea within the normal range, nevertheless after 4 months this function is maintained in essentially the same degree as if both kidneys were present. This does not imply that all activities of the kidney remaining after unilateral nephrectomy are potentially augmented, but the data offered justify the conclusion that as the remaining kidney undergoes enlargement its functional capacity increases and the process represents a genuine hypertrophy in the critical sense.