Artikel
Uric Acid Levels are associated with Endothelium-dependent Vasodilatation in Subjects with Essential Hypertension
Harnsäure-Spiegel sind assoziiert mit endothelabhängiger Vasodilatation bei Patienten mit essentieller Hypertonie
Suche in Medline nach
Autoren
Veröffentlicht: | 11. November 2004 |
---|
Gliederung
Text
Objective
Uric acid levels are elevated in subjects at high cardiovascular risk and are linked to an increased rate of cardiovascular events. The mechanism, however, has not been elucidated yet. Impaired endothelium-dependent vasodilation in the forearm vasculature has also been linked to an elevated cardiovascular risk in hypertensive subjects. We therefore hypothesized that uric acid levels may be associated with altered endothelium-dependent vasodilation.
Methods
In 60 hypertensive subjects and in 20 normotensive controls, endothelium-dependent and -independent vasodilation were assessed by plethysmographic monitoring of forearm blood flow responses (FBF) to intraarterial infusion of acetylcholine (Ach) at doses of 12 and 48 mg/min and nitroprusside at doses of 3.2 and 12.8 mg/min, respectively. NG-monomethyl-L-arginine (L-NMMA) was infused to analyse nitric oxide (NO) mediated basal vascular tone at doses of 4, 8 and 16 mmol/min.
Results
Uric acid levels tended to be higher in hypertensive than in normotensive subjects (5.5±1.4 versus 4.8±1.5 mg/dl, p=0.08). Uric acid levels were associated with an impaired FBF response to Ach 12 mg/min (r=-0.33, p=0.003) and to 48 mg/min (r=-0.29, p=0.009) but were not associated with the reponses to nitroprusside and L-NMMA. In the group of hypertensive subjects, the correlation remained significant (DAch 12 mg/min: r=-0.32, p=0.013 and DAch 48 mg/min: r=-0.29, p=0.023, respectively). In the group of normotensive subjects, however, no correlation between uric acid levels and endothelium-dependent vasodilation was found.
Conclusion
Uric acid levels are linked to impaired endothelium-dependent vasodilation in subjects with essential hypertension. Elevated uric acid levels may therefore increase cardiovascular risk by altering endothelium-dependent vasodilation.