Saini A, Berry C, Greenwald S
Department of Morbid Anatomy, London Hospital Medical College, UK.
J Vasc Res. 1995 Nov-Dec;32(6):398-405. doi: 10.1159/000159115.
When ring segments of artery free of external loads are cut longitudinally, they spring open. This property which has been termed residual strain, is a manifestation of an underlying residual stress and may be quantified by measuring the degree to which the cut ring springs open. Residual stress serves to redistribute the forces in the media and to minimize the stress gradient between its inner and outer margins. Its magnitude and distribution are closely related to vascular growth and development. We have measured the degree of opening (in terms of an opening angle, see below for its definition) in 168 rings removed from six positions along aortae obtained at autopsy from 30 subjects aged between 3 months and 87 years. At all ages, there was an overall increase in opening angle along the aorta away from the heart. At all positions, the opening angle increased with age and was higher in vessels with visible atheroma. At all ages, the opening angle was significantly greater in males than in females. This difference persisted when allowance was made for the greater incidence of atheroma in males. We have found a similar age-related increase in rats, although there was no difference between males and females. These observations are consistent with a recently proposed 'stress-growth' law in which remodelling of the arterial wall is driven by the non-uniform distribution of stress across it and may be associated with known sex-related differences in the aetiology of cardiovascular disease.
当去除外部负荷的动脉环形节段被纵向切开时，它们会弹开。这种特性被称为残余应变，是潜在残余应力的一种表现，可以通过测量切开的环弹开的程度来量化。残余应力有助于重新分布中膜中的力，并使内膜和外膜之间的应力梯度最小化。其大小和分布与血管的生长和发育密切相关。我们测量了从30名年龄在3个月至87岁之间的受试者尸检获得的主动脉六个位置取下的168个环的开口程度（以开口角度表示，其定义见下文）。在所有年龄段，沿着远离心脏的主动脉，开口角度总体上都有所增加。在所有位置，开口角度随年龄增加而增加，并且在有明显动脉粥样硬化的血管中更高。在所有年龄段，男性的开口角度明显大于女性。在考虑到男性动脉粥样硬化发病率较高的情况下，这种差异仍然存在。我们在大鼠中也发现了类似的与年龄相关的增加，尽管雄性和雌性之间没有差异。这些观察结果与最近提出的“应力-生长”定律一致，该定律认为动脉壁的重塑是由应力在其上的不均匀分布驱动的，并且可能与心血管疾病病因学中已知的性别相关差异有关。
