Effect of a hemodialysis session on plasma levels of endothelin-1 in hypertensive and normotensive subjects with end-stage renal failure

Background: Elevated plasma endothelin-1 (ET-1) was found in end-stage rena l failure (ESRF). However, there are discordant reports on the influence of hypertension on plasma ET-1 in ESRF and on the effect of hemodialysis on E T-1 concentrations. Aim: To compare the time course of plasma ET-1 during h emodialysis in hypertensive (HT) and normotensive (NT) ESRF patients. Metho ds: Plasma ET-1 and mean blood pressure (MP) were measured in 12 HT patient s and 11 matched NT patients on maintenance hemodialysis at baseline (B), a fter a 2.5-3.5 h hemodialysis with ultrafiltration (P1) and after a subsequ ent 1 h isovolumic dialysis (P2). Results: In HT patients, plasma ET-1 incr eased at P1 with no further change after P2 (B vs. P1 and P2, p < 0.05). In NT patients, ET-1 levels were similar at B, P1 and P2. In HT, but not in N T subjects, volume loss correlated with change of ET-1 at P1. In HT patient s, MP fell during P1 and tended to return towards baseline at P2. In NT pat ients, MP dropped after P1 and remained lower also at P2. Conclusion: Hyper tensive ESRF subjects exhibit potentiated ET-1 release on hemodialysis, pos sibly stimulated by volume depletion with sympathetic activation, which may attenuate hypotensive hemodialysis effects thus contributing to hypertensi on in ESRF.