[Compensatory hypertrophy of the kidney. Experimental data and applications to man (author's transl)]

Compensatory hypertrophy of the kidney is a puzzling phenomenon of considerable importance, as it makes it possible for a patient with one kidney absent, destroyed or removed to lead a normal life. Non wonder then that since the beginning of the century it has given rise to numerous studies, first on animals, then on live renal transplant donors. The increase in volume of the remaining kidney is not due to an increase in the number of nephrons, but to hyperplasia and, mostly, hypertrophy of the cells of proximal convoluted tubules. Functional adaptation essentially results from increased tubular reabsorption but also involves all other kidney functions, so that the overall renal function of subjects with only one kidney is almost the same as that of subjects with two kidneys. The mechanism which triggers off compensatory hypertrophy remains unclear, and several theories still need to be confirmed.