脱细胞肝素处理犬颈动脉的异种移植研究

目的：研究用去污剂-酶消化联合肝素结合处理法制备小口径异种移植血管.方法：犬颈动脉管壁经脱细胞后部分再行肝素结合处理,样本经组织学及电镜观察脱细胞效果,机械性能研究观察脱细胞对管壁弹性和强度的影响,甲苯胺蓝染色观察肝素结合效果和结合程度.将结合与未结合肝素的脱细胞血管同时植入16只兔双侧颈动脉,术后21 d B超观察移植血管的通畅情况.结果：犬颈动脉血管壁细胞被完全去除,细胞外基质保存完好,机械性能无明显破坏,肝素结合于管壁全层,植入兔颈动脉后两侧均无血管阻塞,而肝素结合组血栓形成少于未结合组.结论：去污剂-酶消化法联合肝素结合处理可以作为制备脱细胞小口径异种移植血管的新方法.

Preparation of a new vascular xenograft: a decellularized and heparinized canine carotid artery transplanted into the rabbits

Objective To explore a new small-caliber vascular xenograft bypass by enzymatic-detergent extraction and heparin linkage procedure. Methods Canine carotid arteries were decellularized by enzymatic-detergent extraction. Some decellularized vascular grafts were covalently linked with heparin to reduce thrombogeneity. Histology and electron microscopic examination were used to confirm the removal of cells. Mechanical testing of the grafts was also performed. The efficiency of heparin linkage was demonstrated with toluidine blue staining. Decellularized grafts with or without heparinization were implanted into the rabbits as bilateral carotid artery bypass grafts and the graft patency was examined by uhrasonography after 3 weeks. Results All the cells were removed with the well-preserved extracellular matrix. The mechanical properties were not destroyed significantly. Heparin was successfully linked to the grafts throughout the entire wall. No obstruction was observed at both sides after implantation. And less thrombi were found in the decellularized and heparinized grafts than those in the grafts without heparinization. Conclusions The method by enzymatic-detergent extraction and heparin linkage is a new strategy to prepare a small-caliber vascular xenograft.