RECOMBINANT-HUMAN-ERYTHROPOIETIN DOES NOT REGULATE THE EXPRESSION OF ENDOTHELIN-1 AND CONSTITUTIVE NITRIC-OXIDE SYNTHASE IN VASCULAR ENDOTHELIAL-CELLS

Erythropoietin (rHuEPO)-induced hypertension represents a clinical pro blem in hemodialysis units. However, the underlying molecular mechanis ms of this side effect are still unclear. In order to assess the poten tial participation of the endothelial-derived vasoactive factors, nitr ic oxide and endothelin-1, bovine aortic endothelial cells were incuba ted in the presence of rHuEPO. The latter (0.1-10 U/ml, 1-24 h) did no t modify the synthesis of nitric oxide and endothelin-1 or the express ion of nitric oxide synthase and pre-pro-endothelin-1 mRNAs. These res ults suggest that endothelial-derived vasoactive factors are not a key component in the hypertensive response observed in certain patients a fter the administration of rHuEPO.