Impact of Hemodialysis-Induced Hemoglobin Release Studied
Hemoglobin release associated with nitric oxide scavenging and endothelial dysfunction
WEDNESDAY, Jan. 27 (HealthDay News) -- Hemoglobin released after hemodialysis is associated with nitric oxide scavenging and worse endothelial function, according to a study in the Feb. 2 issue of the Journal of the American College of Cardiology.
Christian Meyer, M.D., from University Hospital in Duesseldorf, Germany, and colleagues measured the bioavailability of nitric oxide, as well as endothelial function, in 14 patients with end-stage renal disease on chronic hemodialysis before and after treatment.
The researchers found that hemodialysis impaired endothelial function, with a significant reduction in flow-mediated dilation of the brachial artery that did not affect the diameter of the artery. Cell-free plasma hemoglobin levels significantly increased after treatment, reducing the bioavailability of free nitric oxide by more than 70 percent due to oxidation by the released hemoglobin. Higher levels of released hemoglobin after hemodialysis were significantly associated with reduced endothelial function.
"Our data support a role of hemodialysis-induced release of hemoglobin in the pathogenesis of endothelial dysfunction in patients with end-stage renal disease," Meyer and colleagues conclude. "Approaches that oxidize free plasma hemoglobin may restore nitric oxide bioavailability and may have potential beneficial effects on vascular function."