Ursodeoxycholic acid and endothelial‐dependent, nitric oxide‐independent vasodilatation of forearm resistance arteries in patients with coronary heart disease

AIMS: Ursodeoxycholic acid (UDCA) has cholesterol lowering and anti-inflammatory effects and bile acids are reported to exert vasodilator effects; all of these properties might be considered desirable in a drug used in the treatment of patients with coronary heart disease. We investigated a hypothesis that UDCA may dilate arteries and the mechanism of action. METHODS: We evaluated effects of a 6-week treatment with UDCA in 11 coronary heart disease patients on endothelium-dependent (acetylcholine-induced) and -independent (nitroprusside-induced) vasodilatations in forearm vasculature by strain-gauge plethysmography. Healthy individuals (n=14) served as baseline controls. RESULTS: The percentage increase by acetylcholine in the flow of the infused arm relative to the non-infused arm of coronary heart disease patients during the trial remained unaltered, but vasodilatation to NG-monomethyl-l-arginine+acetylcholine was improved by 161+/-27% with UDCA vs 83+/-22% with placebo (mean difference 91% 95% CI 35%, 147%, P=0.016). CONCLUSIONS: Six weeks' UDCA therapy improved endothelium-dependent nitric oxide-independent vasodilatation, which might maintain arterial flow in coronary heart disease patients under conditions of impaired nitric oxide production.