Plasma renin and aldosterone after renal transplantation

Abstract

Plasma renin activity (PRA) and plasma aldosterone (PA) were measured in 19 renal allograft recipients during the first month after transplantation. PRA and PA were elevated in most patients during the first days. The values were significantly higher in patients with late onset of graft function than in patients whose kidneys worked well from the transplantation on. After three to four weeks most PRA and all PA values were within the normal ranges. It is suggested that the ischemia during transplantation is the cause of renin elevation. Elevation of PA is most likely the consequence of increased angiotensin II generated by high PRA, indicating that the renin angiotensin aldosterone relationship is unaltered in many patients after renal transplantation. A dissociation between PRA and PA was observed in several cases. Similar observations have been made in patients with terminal renal failure. The phenomenon cannot be fully explained. Significant increases in PRA and PA were observed after 2 hr of ambulation demonstrating that the postural renin response is unaltered in transplanted and, thus, denervated kidneys. No consistent relationship between acute graft rejection and PRA could be demonstrated. There was no significant correlation between PRA and blood pressure after transplantation.