Roy Sylvain, Silacci Paolo, Stergiopulos Nikolaos
Swiss Federal Institute for Technology, CH-1015 Lausanne, Switzerland.
Am J Physiol Heart Circ Physiol. 2005 Oct;289(4):H1567-76. doi: 10.1152/ajpheart.00564.2004. Epub 2005 May 20.
To analyze the effects of decellularization on the biomechanical properties of porcine common carotid arteries, decellularization was performed by a detergent-enzymatic procedure that preserves extracellular matrix scaffold. Internal diameter, external diameter, and wall thickness were measured by optical microscopy on neighboring histological sections before and after decellularization. Rupture tests were conducted. Inner diameter and wall thickness were measured by echo tracking during pressure inflation from 10 to 145 mmHg. Distensibility and incremental elastic modulus were computed. At 10 mmHg, mean diameter of decellularized arteries was 5.38 mm, substantially higher than controls (4.1 mm), whereas decellularized and control arteries reached the same internal diameter (6.7 mm) at 145 mmHg. Wall thickness decreased 16% for decellularized and 32% for normal arteries after pressure was increased from 10 to 145 mmHg. Decellularized arteries withstood pressure >2,200 mmHg before rupture. At 145 mmHg, decellularization reduced compliance by 66% and increased incremental elastic modulus by 54%. Removal of cellular elements from media led to changes in arterial dimensions. Collagen fibers engaged more rapidly during inflation, yielding a stiffer vessel. Distensibility was therefore significantly lower (by a factor of 3) in decellularized than in normal vessels: reduced in the physiological range of pressures. In conclusion, decellularization yields vessels that can withstand high inflation pressures with, however, markedly different geometrical and biomechanical properties. This may mean that the potential use of a decellularized artery as a scaffold for the creation of xenografts may be compromised because of geometrical and compliance mismatch.
为分析去细胞处理对猪颈总动脉生物力学特性的影响，采用一种能保留细胞外基质支架的去污剂 - 酶法进行去细胞处理。在去细胞处理前后，通过光学显微镜在相邻组织切片上测量内径、外径和壁厚。进行破裂试验。在压力从10 mmHg 升至145 mmHg 的过程中，通过回声跟踪测量内径和壁厚。计算扩张性和增量弹性模量。在10 mmHg 时，去细胞动脉的平均直径为5.38 mm，显著高于对照组（4.1 mm），而在145 mmHg 时，去细胞动脉和对照动脉达到相同的内径（6.7 mm）。当压力从10 mmHg 升至145 mmHg 时，去细胞动脉的壁厚减少了16%，正常动脉的壁厚减少了32%。去细胞动脉在破裂前能承受大于2200 mmHg 的压力。在145 mmHg 时，去细胞处理使顺应性降低了66%，增量弹性模量增加了54%。从血管中层去除细胞成分导致动脉尺寸发生变化。在膨胀过程中，胶原纤维更快地参与进来，使血管更硬。因此，去细胞血管的扩张性显著低于正常血管（降低了3倍）：在生理压力范围内降低。总之，去细胞处理产生的血管能够承受高膨胀压力，然而，其几何和生物力学特性明显不同。这可能意味着，由于几何形状和顺应性不匹配，去细胞动脉作为异种移植物支架的潜在用途可能会受到影响。
