S-EPMC5099003 - Influence of shear stress magnitude and direction on atherosclerotic plaque composition. - OmicsDI

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Influence of shear stress magnitude and direction on atherosclerotic plaque composition.

ABSTRACT: The precise flow characteristics that promote different atherosclerotic plaque types remain unclear. We previously developed a blood flow-modifying cuff for ApoE-/- mice that induces the development of advanced plaques with vulnerable and stable features upstream and downstream of the cuff, respectively. Herein, we sought to test the hypothesis that changes in flow magnitude promote formation of the upstream (vulnerable) plaque, whereas altered flow direction is important for development of the downstream (stable) plaque. We instrumented ApoE-/- mice (n?=?7) with a cuff around the left carotid artery and imaged them with micro-CT (39.6?µm resolution) eight to nine weeks after cuff placement. Computational fluid dynamics was then performed to compute six metrics that describe different aspects of atherogenic flow in terms of wall shear stress magnitude and/or direction. In a subset of four imaged animals, we performed histology to confirm the presence of advanced plaques and measure plaque length in each segment. Relative to the control artery, the region upstream of the cuff exhibited changes in shear stress magnitude only (p?

SUBMITTER: Pedrigi RM

PROVIDER: S-EPMC5099003 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Influence of shear stress magnitude and direction on atherosclerotic plaque composition.

Pedrigi Ryan M RM Mehta Vikram V VV Bovens Sandra M SM Mohri Zahra Z Poulsen Christian Bo CB Gsell Willy W Tremoleda Jordi L JL Towhidi Leila L de Silva Ranil R Petretto Enrico E Krams Rob R

Royal Society open science 20161019 10

The precise flow characteristics that promote different atherosclerotic plaque types remain unclear. We previously developed a blood flow-modifying cuff for ApoE<sup>-/-</sup> mice that induces the development of advanced plaques with vulnerable and stable features upstream and downstream of the cuff, respectively. Herein, we sought to test the hypothesis that changes in flow magnitude promote formation of the upstream (vulnerable) plaque, whereas altered flow direction is important for developm ...[more]

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