Ferruzzi J, Bersi M R, Mecham R P, Ramirez F, Yanagisawa H, Tellides G, Humphrey J D
Department of Biomedical Engineering, Yale University, New Haven, CT, USA.
Department of Cell Biology, Washington University, St. Louis, MO, USA.
Artery Res. 2016 Jun;14:41-52. doi: 10.1016/j.artres.2016.04.001. Epub 2016 Apr 22.
Competent elastic fibers endow central arteries with the compliance and resilience that are fundamental to their primary mechanical function in vertebrates. That is, by enabling elastic energy to be stored in the arterial wall during systole and then to be used to work on the blood during diastole, elastic fibers decrease ventricular workload and augment blood flow in pulsatile systems. Indeed, because elastic fibers are formed during development and stretched during somatic growth, their continual tendency to recoil contributes to the undulation of the stiffer collagen fibers, which facilitates further the overall compliance of the wall under physiologic pressures while allowing the collagen to limit over-distension during acute increases in blood pressure. In this paper, we use consistent methods of measurement and quantification to compare the biaxial material stiffness, structural stiffness, and energy storage capacity of murine common carotid arteries having graded degrees of elastic fiber integrity - normal, elastin-deficient, fibrillin-1 deficient, fibulin-5 null, and elastase-treated. The finding that the intrinsic material stiffness tends to be maintained nearly constant suggests that intramural cells seek to maintain a favorable micromechanical environment in which to function. Nevertheless, a loss of elastic energy storage capability due to the loss of elastic fiber integrity severely compromises the primary function of these central arteries.
功能正常的弹性纤维赋予中枢动脉顺应性和弹性，这对于它们在脊椎动物中的主要机械功能至关重要。也就是说，通过在收缩期使弹性能量存储在动脉壁中，然后在舒张期用于作用于血液，弹性纤维降低了心室负荷并增加了脉动系统中的血流量。实际上，由于弹性纤维在发育过程中形成并在体细胞生长过程中被拉伸，它们持续的回缩倾向有助于更硬的胶原纤维的起伏，这在生理压力下进一步促进了血管壁的整体顺应性，同时允许胶原在血压急性升高时限制过度扩张。在本文中，我们使用一致的测量和量化方法来比较具有不同程度弹性纤维完整性的小鼠颈总动脉的双轴材料刚度、结构刚度和能量存储能力——正常、弹性蛋白缺陷、原纤蛋白-1缺陷、纤连蛋白-5缺失和弹性蛋白酶处理的。内在材料刚度趋于几乎保持恒定这一发现表明壁内细胞试图维持一个有利于其发挥功能的微机械环境。然而，由于弹性纤维完整性丧失导致的弹性能量存储能力丧失严重损害了这些中枢动脉的主要功能。
