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An integrated set-up for ex vivo characterisation of biaxial murine artery biomechanics under pulsatile conditions.

ABSTRACT: Ex vivo characterisation of arterial biomechanics enables detailed discrimination of the various cellular and extracellular contributions to arterial stiffness. However, ex vivo biomechanical studies are commonly performed under quasi-static conditions, whereas dynamic biomechanical behaviour (as relevant in vivo) may differ substantially. Hence, we aim to (1) develop an integrated set-up for quasi-static and dynamic biaxial biomechanical testing, (2) quantify set-up reproducibility, and (3) illustrate the differences in measured arterial stiffness between quasi-static and dynamic conditions. Twenty-two mouse carotid arteries were mounted between glass micropipettes and kept fully vasodilated. While recording pressure, axial force (F), and inner diameter, arteries were exposed to (1) quasi-static pressure inflation from 0 to 200 mmHg; (2) 300 bpm dynamic pressure inflation (peaking at 80/120/160 mmHg); and (3) axial stretch (?_z) variation at constant pressures of 10/60/100/140/200 mmHg. Measurements were performed in duplicate. Single-point pulse wave velocities (PWV; Bramwell-Hill) and axial stiffness coefficients (c_ax?=?dF/d?_z) were calculated at the in vivo value of ?_z. Within-subject coefficients of variation were?~?20%. Dynamic PWVs were consistently higher than quasi-static PWVs (p?ax increased with increasing pressure. We demonstrated the feasibility of ex vivo biomechanical characterisation of biaxially-loaded murine carotid arteries under pulsatile conditions, and quantified reproducibility allowing for well-powered future study design.

SUBMITTER: van der Bruggen MM

PROVIDER: S-EPMC7846753 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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An integrated set-up for ex vivo characterisation of biaxial murine artery biomechanics under pulsatile conditions.

van der Bruggen Myrthe M MM Reesink Koen D KD Spronck Paul J M PJM Bitsch Nicole N Hameleers Jeroen J Megens Remco T A RTA Schalkwijk Casper G CG Delhaas Tammo T Spronck Bart B

Scientific reports 20210129 1

Ex vivo characterisation of arterial biomechanics enables detailed discrimination of the various cellular and extracellular contributions to arterial stiffness. However, ex vivo biomechanical studies are commonly performed under quasi-static conditions, whereas dynamic biomechanical behaviour (as relevant in vivo) may differ substantially. Hence, we aim to (1) develop an integrated set-up for quasi-static and dynamic biaxial biomechanical testing, (2) quantify set-up reproducibility, and (3) ill ...[more]

PMID: 33514757

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Dataset Information

An integrated set-up for ex vivo characterisation of biaxial murine artery biomechanics under pulsatile conditions.

Publications

An integrated set-up for ex vivo characterisation of biaxial murine artery biomechanics under pulsatile conditions.

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