聚四氟乙烯纳米化新型小口径人造血管及其通畅率研究

目的 研究应用内表面覆盖多壁碳纳米管（MWNT）的聚四氟乙烯（PTFE）新型人造血管（PTFE-MWNT）对提高血管通畅率、减轻内膜增生的影响.方法 将MWNTs通过羧酸化及氨基化处理,分别得到功能化的MWNTs-COOH和MWNTs-NH2,然后在PTFE血管内表面层层自组装制成PTFE-MWNT人造血管.动脉模型选用羊股动脉血管移植.16只成年公绵羊,两侧股动脉随机选用两种不同的人造血管.8只于术后3个月,另外8只于术后9个月取下双侧人造血管标本进行组织学分析.统计方法采用配对t检验.结果 PTFE-MWNT血管术后通畅率（87.5%）高于PTFE血管（62.5%）,内膜增生程度较PTFE血管轻,血管内皮形成速度要快于PTFE人造血管,血管壁内的炎细胞浸润较轻;而PTFE人造血管壁内主要是炎细胞浸润,细胞增殖程度高于PTFE-MWNT人造血管.结论 用多壁碳纳米管覆盖聚四氟乙烯的内表面制成的新型人造血管,可以提高移植血管通畅率,减轻内膜增生,提高小口径人造血管移植手术的长期效果.

Research on the patency of new small-caliber PTFE vascular graft coated with carbon nanotube in the inner wall

Objective A new type of vascular graft made from coating the inner wall of PTFE graft with muhi-walled nanotubes （PTFE-MWNT） was implanted in adult sheep＇s bilateral femoral arteries to evaluate the difference outcome of the postoperative graft patency rate and the extent of intimal hyperplasia. Methods The functionalized MWNT-COOH and MWNT-NH2 are synthesized via acidification and amination. The MWNTs film was self-assembled on the inner wall of the PTFE grafts layer-by-layer. Sixteen adult sheep were implanted with vascular grafts in their bilateral femoral arteries. A PTFE-MWNT graft or PTFE graft was implanted into which side of femoral arteries randomly. The specimens of vascular grafts harvested 3 months postoperatively in 8 sheep and 9 months postoperatively in the other 8 were histologically analyzed. Statistical analysis was performed with the paired t test. Results There appeared higher patency rate in PTFE-MWNT grafts and less intimal hyperplasia compared with PTFE grafts. Less inilammatory cells infiltration was observed in PTFE-MWNT grafts. And the en- dothelium formation was more quickly and completely in PTFE-MWNT grafts than in, FIFE grafts. Furthermore, there were more cells in proliferation in PTFE grafts. Conclusion The utility of this new type of vascular grafts made from PTFE grafts coated with MWNT in the inner wall can increase the graft patency rate and decrease the extent of intimal hyperplasia postoperatively, indicating a hopeful method for improving the long-term outcome of the small size vascular graft implantation.