[Renal response to acute expansion of the extracellular volume in renal transplant patients].

The response to acute isotonic saline loading (1 800 ml in 3 hours) was assessed in 12 normotensive and 11 hypertensive renal transplant recipients. Both groups had similar renal function, daily urinary excretion of sodium and doses of steroids. The natriuretic response to saline was not affected in hypertensive transplants and changes in blood pressure, renin and aldosterone were identical in both groups. Similar correlations between pre-saline fractional excretion of sodium (FENa+) and the FENa+ obtained during saline were obtained in normotensive and hypertensive patients. These results demonstrate that in renal transplant recipients of young donors no exaggeration of the response to saline occurs in hypertensive subjects thus suggesting that normal kidneys may carry their characteristics when transplanted in a new environment. The role of renal denervation remains unclear.