Alterations in Carotid Parameters in ApoE-/- Mice Treated with a High-Fat Diet: A Micro-ultrasound Analysis.

Information on the common carotid artery and cerebral microcirculation can be obtained by micro-ultrasound (µUS). The aim of the study described here was to investigate high-fat diet-induced alterations in vascular parameters in ApoE-/- mice. Twenty-two ApoE-/- male mice were examined by µUS and divided into the standard diet (ApoE-/-) and high-fat diet (ApoE-/-) groups. The µUS examination was repeated after 4 mo (T). Carotid stiffness, reflection magnitude and reflection index were measured; the amplitudes of the first (W) and second (W) local maxima, the local minimum (W) and the reflection index (RI = W/W) were assessed with wave intensity analysis. At T, ApoE-/- mice had increased carotid stiffness (1.48 [0.36] vs. 1.88 [0.51]) and reflection magnitude (0.89 [0.07] vs. 0.94 [0.07]) values. Longitudinal comparisons highlighted increases in carotid stiffness for ApoE-/- mice (from 1.37 [0.25] to 1.88 [0.51] m/s) but not for ApoE-/- mice (from 1.40 [0.62] to 1.48 [0.36] m/s). ApoE-/- mice exhibited carotid artery stiffening and increased wave reflections.