仿生型人工小血管支架的构建与体外力学研究

Construction of biomimetic small-diameter artificial scaffold and its biomechanical properties in vitro

目的制备具有三层管壁结构的可降解人工小血管支架，对其生物力学性能进行测试，并与正常生理血管对比以检测其是否符合体内移植试验的要求。方法以可降解的聚对二氧环己酮（PDS）缝合线编织成网管状织物作为血管内支架，模仿天然血管的三层结构，内层共混硫酸软骨素-胶原，外层包被小肠黏膜下层，缝线加固，构建内径〈4mm的小血管支架，检测血管支架的生物力学性能（爆破压力、抗拉伸能力、顺应性等），并与正常生理血管进行比较。结果所制备的人工小血管支架平均内径3．83mm，爆破压为（43．50±8．30）kPa，断裂强度为（19．10±1．56）N，应变率为（42．88±3．16）％，径向顺应性为（5．96±0．87）％／100mmHg（1mmHg=0．133kPa）。结论所制备人工血管的力学性能优良，可以满足动物体内移植试验的要求。

Objective To construct the biomimetic small-diameter artificial scaffold and determine its biomechanical properties in vitro in order to compare with the canine carotid artery for next implantation. Methods The muhilayering scaffold was constructed with polydioxanone （PDS） fibers woven as middle elasticity layer and coved with small intestinal submucosa （ SIS）, and the inner layer was coated with collagen sponge which was mixed with 10% chondroitin sulfate （CS）. Its biomechanieal properties, such as burst strength, rupture intensity, and compliance, were compared with canine carotid artery. Results The average diameter of constructed scaffolds was 3.83 mm, the burst strength of the scaffold was （43.50±8.30） kPa, the rupture intensity was （19. 10 ± 1.56） N, the strain ratio was （42. 88 ± 3.16） % , and the radial compliance was （5.96 ±0.87 ）%/100 mm Hg. Conclusion The scaffold has a satisfactory biomechanical properties that meet the mechanical requirements during the implantation in vivo as a tissue engineered blood vessel scaffold.