Effect of pindolol and propranolol on plasma renin and aldosterone in patients with renal allograft.

To investigate the effect of propranolol and pindolol on renin and aldosterone secretion, blood samples of 12 nephrectomized kidney transplant recipients were taken after 1 hour in supine position and 30 and 60 minutes after posture change. This procedure was repeated after 4 days under pindolol (3 X 5 mg/day) or propranolol (4 X 40 mg/day). Both pindolol and propranolol suppressed the significant orthostatic rise of plasma renin activity (PRA) seen without medication. Pindolol increased basal PRA markedly, whereas basal PRA under propranolol was the same as without betablockers. Plasma aldosterone (PA) showed significant orthostatic rise under all conditions and thus did not parallel PRA under betablockers. Suppression of PRA response to posture change by betablockers indicates that circulating catecholamines may be involved in orthostatic PRA regulation. The intrinsic sympathetic activity of pindolol results in an increase of basal PRA. In nephrectomized renal transplant recipients, postural PA changes do not seem to be triggered by PRA.