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Coronary artery disease (CAD), or atherosclerosis, is responsible for nearly a third of all American deaths annually. Detection of plaques and differentiation of plaque stage remains a complicating factor for treatment. Classification of plaque before significant blockage or rupture could inform clinical decisions and prevent mortality. Current detection methods are either nonspecific, slow, or require the use of potentially harmful contrast agents. Recent advances in hyperspectral imaging could be used to detect changes in the autofluorescence of arteries associated with vessel remodeling and subsequent plaque formation and could detect and classify existing lesions. Here, we present data comparing spectral image characteristics of a mouse model designed to undergo vessel remodeling. C57Bl/6 mice underwent ligation of three of four caudal branches of the left common carotid artery (left external carotid, internal carotid, and occipital artery) with the superior thyroid artery left intact under IACUC approved protocol. Vessels were harvested at a variety of timepoints to compare degrees of remodeling, including 4 weeks and 5 months post-surgery. Immediately following harvest, vessels were prepared by longitudinal opening to expose the luminal surface to a 20X objective. A custom inverted microscope (TE-2000, Nikon Instruments) with a Xe arc lamp and thin film tunable filter arrary (Versachrome, Semrock, Inc.) were used to achieve spectral imaging. Excitation scans utilized wavelengths between 340 nm and 550 nm in 5 nm increments. Hyperspectral data were generated and analyzed with custom Matlab scripts and visualized in ENVI. Preliminary data suggest consistent spectral features associated with control and remodeled vessels. © (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
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Reduced Smooth Muscle Contractile Capacity Facilitates Maladaptive Arterial Remodeling
Abstract Albeit seldom considered explicitly, the vasoactive state of a central artery can contribute to luminal control and thereby affect the in vivo values of flow-induced wall shear stress and pressure-induced intramural stress, which in turn are strong determinants of wall growth and remodeling. Here, we test the hypothesis that diminished vasoactive capacity compromises effective mechano-adaptations of central arteries. Toward this end, we use consistent methods to re-interpret published data on common carotid artery remodeling in a nonpharmacologic mouse model of induced hypertension and a model of connective tissue disorder that results in Marfan syndrome. The mice have identical genetic backgrounds and, in both cases, the data are consistent with the hypothesis considered. In particular, carotid arteries with strong (normal) vasoactive capacity tend to maintain wall thickness and in vivo axial stretch closer to homeostatic, thus resulting in passive circumferential wall stress and energy storage close to normal. We conclude that effective vasoactivity helps to control the biomechanical state in which the cells and matrix turnover, thus helping to delineate mechano-adaptive from maladaptive remodeling. Future analyses of experimental data and computational models of growth and remodeling should account for this strong coupling between smooth muscle contractile capacity and central arterial remodeling.
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- Award ID(s):
- 1760906
- PAR ID:
- 10380578
- Date Published:
- Journal Name:
- Journal of Biomechanical Engineering
- Volume:
- 144
- Issue:
- 4
- ISSN:
- 0148-0731
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.4052888
