Renin responsiveness to furosemide in the homotransplanted kidney

Plasma renin activity (PRA) was measured after repetitive furosemide stimulations in 16 normotensive homotransplanted patients who previously had bilateral nephrectomies. The percentage PRA response to furosemide was very low (34%) in the immediate period after transplantation, but increased progressively with time to a level after one year (111%) which was not statistically different from age and sex matched control subjects. A significant correlation was found between the percentage PRA increase and the number of weeks after transplantation (r = 0.48, P less than 0.01). These data indicate that the juxtaglomerular cell responsiveness to furosemide is quantitatively time dependent after transplantation, and it is a factor that should be considered in the evaluation of renin-angiotensin system in such patients.