Format

Send to

Choose Destination
J Am Coll Cardiol. 2010 Feb 2;55(5):454-9. doi: 10.1016/j.jacc.2009.07.068.

Hemodialysis-induced release of hemoglobin limits nitric oxide bioavailability and impairs vascular function.

Author information

1
Division of Cardiology, Pulmonology and Vascular Medicine, University Hospital, Duesseldorf, Germany.

Abstract

OBJECTIVES:

This study sought to characterize the impact of hemodialysis (HD)-induced release of hemoglobin on the bioavailability of nitric oxide (NO) and endothelial function.

BACKGROUND:

Patients on chronic HD suffer from endothelial dysfunction and a massively increased risk for cardiovascular events. Although dialysis-dependent and -independent factors are discussed, the exact mechanisms are not fully understood.

METHODS:

In 14 HD patients (56+/-15 years of age), endothelial function was determined by measuring flow-mediated dilation (FMD) of the brachial artery using high-resolution ultrasound before and after treatment. The NO consumption activity of plasma isolated from patients before and after hemodialysis was studied with an NO-sensitive electrode.

RESULTS:

HD impaired FMD (3.5+/-2.6% to 1.7+/-1.4%, p=0.04) without affecting brachial artery diameter (4.7+/-0.6 mm vs. 4.4+/-0.9 mm, p=0.27). This was accompanied by an increase in cell-free plasma hemoglobin (196+/-43 mg/l to 285+/-109 mg/l, p=0.01), which led to a decrease in the bioavailability of free NO by more than 70%. Oxidation of the released plasma ferrous hemoglobin prevented the consumption of NO. The amount of decompartmentalized hemoglobin after HD correlated inversely with the change in FMD (r=-0.65, p=0.041).

CONCLUSIONS:

Our data support a role of HD-induced release of hemoglobin in the pathogenesis of endothelial dysfunction in patients with end-stage renal disease. Approaches that oxidize free plasma hemoglobin may restore NO bioavailability and may have potential beneficial effects on vascular function. (Influence of Hemodialysis on Endothel-Depending Dilatation of Peripheral Arteries; NCT00764192).

PMID:
20117459
DOI:
10.1016/j.jacc.2009.07.068
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center