Abstract
Pathomechanism of erythropoietin (EPO) dependent hypertension remained to be elucidated. This study was undertaken to appreciate a participation of two main vasoactive substances, e. g. endothelin (ET-1) and nitric oxide (NOx), in EPO-dependent hypertension.
Plasma level of ET-1 as well s NOx were measured monthly over 3 months after recombinant human erythropoietin (r-HuEPO) therapy in 11 hemodialysis patients. In addition, two vascular markers, e. g. thrombomodulin (TM), tissue factor (TF), were simultaneously determined. Elevation of mean arterial pressure (MAP) more than 5mmHg was found in 5 out of 11 cases after r-HuEPO therapy. Plasma level of ET-1 and NOx showed neither significant variation in time course nor significant difference with variation in MAP after r-HuEPO therapy. ET-1/NOx ratio was slightly, but not significantly, lowered after r-HuEPO therapy in patient whose MAP didn't increase (p=0.116). We also could'nt confirm a correlation between ΔET-1/ΔNOx and ΔMAP. As for plasma level of TM and TF, both of which increased at basal point, but no significant variation could be found through 3 months of r-HuEPO treatment (r=0.314, p=0.076)
Although this study failed to show a clear evidence for the role of either NO or ET-1 in the pathomechanism of EPO-dependent hypertension, we considered it desereved to be studied in clinical setting of more expanding cases.
