Department of Cardio-thoracic Surgery, Shanghai Sixth People Hospital, Shanghai Jiao Tong University School of Medicine, China.
Acta Biochim Biophys Sin (Shanghai). 2011 Jun;43(6):433-40. doi: 10.1093/abbs/gmr034. Epub 2011 May 12.
The aim of this study was to explore the in vivo behavior and histocompatibility of poly(trimethylene carbonate-co-D,L-lactide) (PDLLA/TMC) and its feasibility of manufacturing cardiovascular stents. Copolymers with 50/50 molar ratio were synthesized by ring-opening polymerization with TMC and D, L-LA, or TMC and L-LA. Poly(L-lactide) (PLLA) was synthesized as a control. The films of the three polymers were implanted into 144 Wistar rats. At different time points of implantation, polymer films were explanted for the evaluation of degradation characteristics and histocompatibility using size exclusion chromatography , nuclear magnetic resonance , environmental scanning electron microscope , and optical microscope. Results showed that there were differences in the percentage of mass loss, molecular weight, shape and appearance changes, and inflammation cell counts between different polymers. With the time extended, the film's superficial structure transformed variously, which was rather obvious in the polymer of PDLLA/TMC. In addition, there were relatively lower inflammation cell counts in the PDLLA/TMC and poly(trimethylene carbonate-co-L-lactide) (PLLA/TMC) groups at different time points in comparison with those in the PLLA group. The differences were of statistical significance (P< 0.05) in the group of PDLLA/TMC vs. PLLA, and the group of PLLA/TMC vs. PLLA, but not within the PDLLA/TMC and PLLA/TMC groups (P> 0.05). These results suggested that the polymer of PDLLA/TMC (50/50) with favorable degradation performance and histocompatibility is fully biodegradable and suitable for manufacturing implanted cardiovascular stents.
本研究旨在探讨聚（三亚甲基碳酸酯-共-D,L-丙交酯）（PDLLA/TMC）的体内行为和组织相容性及其制造心血管支架的可行性。采用开环聚合，以 TMC 和 D,L-丙交酯或 TMC 和 L-丙交酯为原料合成摩尔比为 50/50 的共聚物。合成聚（L-丙交酯）（PLLA）作为对照。将三种聚合物的薄膜植入 144 只 Wistar 大鼠体内。在不同的植入时间点，取出聚合物薄膜进行降解特性和组织相容性评价，采用凝胶渗透色谱、核磁共振、环境扫描电子显微镜和光学显微镜。结果表明，不同聚合物的质量损失百分比、分子量、形状和外观变化以及炎症细胞计数存在差异。随着时间的延长，薄膜的表面结构发生了各种变化，在 PDLLA/TMC 聚合物中更为明显。此外，与 PLLA 组相比，PDLLA/TMC 和聚（三亚甲基碳酸酯-共-L-丙交酯）（PLLA/TMC）组在不同时间点的炎症细胞计数相对较低。PDLLA/TMC 组与 PLLA 组、PLLA/TMC 组与 PLLA 组之间的差异有统计学意义（P<0.05），但 PDLLA/TMC 组和 PLLA/TMC 组之间无差异（P>0.05）。这些结果表明，具有良好降解性能和组织相容性的 PDLLA/TMC（50/50）聚合物是完全可生物降解的，适用于制造植入式心血管支架。
