Haemodynamically significant plaque formation and regional endothelial dysfunction in cholesterol-fed ApoE−/− mice

Autor: JOHANSSON, Maria E., HÄGG, Ulrika, WIKSTRÖM, Johannes, WICKMAN, Anna, BERGSTRÖM, Göran, GAN, Li-ming
Zdroj: Clinical Science; June 2005, Vol. 108 Issue: 6 p531-538, 8p
Abstrakt: Flow-mediated vasodilation is suggested as one of the mechanisms involved in arterial expansive remodelling, which is thought to be a defence mechanism in atherogenesis. In the present study, we tested the hypothesis that lumen obstructive plaque formation is associated with failure of NO (nitric oxide)-dependent vasodilation in conduit vessels. Cardiac function and aortic root flow velocities were assessed using high-resolution echocardiography and two-dimensional-guided pulsed Doppler in ApoE−/− (apolipoprotein E-deficient) mice fed a standard or high-cholesterol diet. Endothelial function in the proximal and mid-descending aortic regions was studied using a myograph technique. Flow velocity at the aortic root of cholesterol-fed ApoE−/− mice was significantly increased as a result of lumen narrowing, detected via histological analysis. NO-dependent vasodilatory responses were selectively impaired in the atherosclerosis-prone vascular regions in cholesterol-fed ApoE−/− mice. In conclusion, consumption of a high-cholesterol diet results in lumen obstructive plaque formation in ApoE−/− mice, which significantly alters aortic root haemodynamics. This phenomenon is associated with impaired NO-dependent vasodilation in vessel segments known to be prone to atherosclerosis.
Databáze: Supplemental Index