磷酰胆碱接枝Dacron人工血管移植后血管表面的生物相容性

Surface biocompatibility of Dacron vascular prosthesis coated with phosphorylcholine

背景:前期研究发现涤纶人工血管经接枝2-甲基丙稀酰氧基乙基磷酰胆碱(2-methacryloyloxyethyl phosphorylcholine,MPC)后,可有效抑制吻合口内膜和平滑肌增生,减少吻合口狭窄程度,增加血流量。目的:通过臭氧活化的方法在Dacron人工血管表面接枝MPC,进一步观察接枝后Dacron人工血管的生物相容性。方法:通过臭氧活化的方法在Dacron人工血管表面接枝MPC,修建成5mm×2mm的椭圆形补片。取新西兰大白兔24只,阻断其腹主动脉,纵形切开腹主动脉前壁,以抽签法随机分为两组:实验组将接枝后的Dacron人工血管作新西兰兔腹主动脉补片移植,对照组移植未接枝Dacron人工血管作对照。于术后1d,1周,2周,4周,进行人工血管苏木精-伊红、Masson染色及扫描电镜观察Dacron人工血管表面内膜增生、血细胞黏附情况。结果与结论:与对照组比较,实验组新内膜增生明显减少,由于Dacron人工血管表面的不平整,未能进行新内膜增生厚度的测量。术后第2周,通过Masson染色在对照组人工血管补片表面观察到新内膜的分层,底层多量细胞浸润,浅层细胞浸润不明显;而实验组未见明显分层现象或者也出现了分层,但底层较薄,附着在Dacron人工血管表面而不明显,这现象持续到术后的第4周。证实在Dacron人工血管补片表面接枝MPC,有效抑制了早期补片表面血栓形成,抑制炎症细胞的浸润,抑制纤维蛋白原的沉积,使早期的新内膜增生减少,较接枝前有更好的生物相容性。

BACKGROUND：Preliminary study found that Dacron vascular prosthesis may inhibit anastomotic intimal and smooth muscle hyperplasia,reduce anastomotic stenosis and increase blood flow by grafting 2-methacryloyloxyethyl phosphorylcholine （MPC）.OBJECTIVE：To study the biocompatibility of Dacron vascular prosthesis coated with 2-MPC by ozonization in rabbit model.METHODS：Dacron vascular prosthesis was grafted with MPC by ozonization and pruned into oval patches at 5 mm × 2 mm.Totally 24 New Zealand rabbits were processed into occluding the abdominal aorta and longitudinally incising the anterior wall of the abdominal aorta.Rabbits were divided into two groups randomly.The treated group was transplanted with Dacron prosthesis grafted MPC,while control group with Dacron prosthesis without MPC graft.At 1 day and 1,2,4 weeks postoperation,rabbits were killed for hematoxylin-eosin staining and Masson staining.Scanning electron microscopy was used to observe the intimal hyperplasia and blood cell adhesion on the surface of Dacron prosthesis.RESULTS AND CONCLUSION：The surface of Dacron vascular prosthesis grafted MPC reduced neointimal proliferation compared with the control group.The thickness of intimal hyperplasia was not measured due to Dacron graft surface was not flat.Stratification of the neointima was found in the control groups at 2 weeks postoperation in Masson staining,and a great deal of cells infiltrated in the lower layer,not obvious in the superficial layer.No obvious stratification in neointima was found in the treated group until 4 weeks.Perhaps it had stratification.The lower lay was so thin than attachment to the Dacron graft surface was not obvious.It is believed that in the Dacron vascular prosthesis grafted MPC,effectively inhibit thrombosis,infiltration of inflammatory cells and deposition of fibrinogen,reduce hyperplasia of neointimal.Dacron vascular prosthesis coated with MPC significantly gets better biocompatibility.