| Project/Area Number |
11680834
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Biomedical engineering/Biological material science
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| Research Institution | Tohoku University |
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Principal Investigator |
MATSUMOTO Takeo Tohoku Univ, Grad Sch Engng, Assoc Prof, 大学院・工学研究科, 助教授 (30209639)
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| Co-Investigator(Kenkyū-buntansha) |
OHASHI Toshiro Tohoku Univ, Grad Sch Engng, Res Associate, 大学院・工学研究科, 助手 (30270812)
SATO Masaaki Tohoku Univ, Grad Sch Engng, Professor, 大学院・工学研究科, 教授 (30111371)
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| Project Period (FY) |
1999 – 2000
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| Project Status |
Completed (Fiscal Year 2000)
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| Budget Amount *help |
¥3,700,000 (Direct Cost: ¥3,700,000)
Fiscal Year 2000: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1999: ¥2,300,000 (Direct Cost: ¥2,300,000)
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| Keywords | biomechanics / atherosclerosis / blood vessel mechanics / pressure-diameter test / mechanical property / ひずみ分布 / 残留応力 |
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| Research Abstract |
To reveal the effects of mechanical factors on the initiation and progression of atherosclerosis, it is important to know the stress and strain distribution in the atherosclerotic lesions as well as the effects of blood flow on the endothelial cells. In this 2-year project, we experimentally induced atherosclerotic lesions in the rabbit thoracic aortas and studied the mechanical environment of the atherosclerotic lesions by measuring their local mechanical properties and local defomation of the aortas during inflation. We first measured local elastic modulus by a pipette aspiration method and studied the relationship between the modulus and the histology quantitatively to find that the atherosclerotic tissue became softer than the normal tissue at the initial stage of the lesion, then became stiffer with the appearance of the smooth muscle cells and calcified tissues. Next, we measured the deformation of the tubular specimen of the aortas during inflation as follows : We made four fine needles penetrate through the wall at an angular interval of about 90゜ as markers and observed the displacement of the needles during inflation from an end of the specimen. Local deformations of the wall were obtained at four circumferential segments held with the two adjacent needles. Strain referring to the stress-free state was obtained for each segment. The strain was not uniform among the segments in the atherosclerotic aorta. The difference among the segments tended to increase with the progression of the disease. Similar measurement performed for human coronary arteries indicated that the segment with thicker plaque had smaller strain. These results indicate that atherosclerotic arteries show marked heterogeneity. Local measurement is indispensable to reveal the mechanical environment of atherosclerotic lesions.
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