Acute Effect of Erythropoietin on Catecholamine Levels in Uremia

Tekin Akpolat, Hacettepe Hastanesi, Nefroloji Bölümü, Hacettepe, TR-06100 Ankara (Turkey) which time the baseline sample was withdrawn. After the baseline sampling at 8.00 a.m., rHuEPO was given intravenously at a dose of 75 U/kg. Blood samples for analysis were taken at 15, 30 and 60 min after the injection and blood pressure readings were recorded simultaneously. Serum ‚L·DOPA, dopamine, norepinephrine and epinephrine levels were measured by highperformance liquid chromatography with electrochemical detection [6]. Student’s Dear Sir, Approximately one third of the patients treated with recombinant erythropoietin (r-HuEPO) will experience either an aggravation of preexisting hypertension or will develop de novo hypertension [1]. But the mechanism is unclear and various causes such as increased blood viscosity and total red cell mass inducing an increase in peripheral resistance [2] and reversal of compensatory va-sodilatation induced by renal anemia [3] have been proposed by several studies before. Besides, some investigators have suggested that r-HuEPO-induced alterations in sympathetic nervous system activity may contribute to the genesis of hypertension during r-HuEPO therapy [4, 5]. In order to clarify the relationship between r-HuEPO and sympathetic activity and determine whether r-HuEPO does have any direct effect on catecholamine levels, we studied serum concentrations of Í^DOPA, do-pamine, norepinephrine and epinephrine after a single dose of r-HuEPO administration in 12 predialysis uremic patients. We included 12 patients with chronic renal failure untreated by dialysis previously (mean age 34.0 years, range 21-68; 5 females and 7 males). The patients had never taken r-HuEPO before and all medications having influence on the sympathetic activity were discontinued 2 weeks before the test. Since catecholamine levels are affected by position,