介孔二氧化硅-雷帕霉素-肝素药物涂层支架生物学性能的研究

Biological properties of mesoporous silica-rapamycin-heparin drug eluting stent

目的构建介孔二氧化硅-雷帕霉素-肝素药物涂层支架(MRHES),通过体内外实验检测其生物学性能。方法用溶血率实验、血小板黏附实验检测其血液相容性。分别将MRHES支架、金属裸支架(BMS)植入到兔一侧颈动脉内。术后在30、90d处死取出标本。将标本分为两段:第一段切片后行苏木精-伊红(HE)染色,观察支架内膜增生;第二段行扫描电镜检查,观察支架表面内皮化。应用SPSS21.0统计软件分析,数据均用均值±标准差(Mean±SD)表示,采用t检验。结果MRHES具有良好的血液相容性。30d后,内膜平均厚度分别为:BMS组:(0.14±0.01)mm,MRHES组:(0.08±0.01)mm,差异有统计学意义(P<0.01)。90d后,内膜平均厚度分别为:BMS组:(0.38±0.04)mm,MRHES组:(0.20±0.03)mm,差异有统计学意义(P<0.01)。30d后BMS组基本完全内皮化而MRHES组内皮化不全,90d后两者均完全内皮化。结论MRHES具有良好的血液相容性,其早期抑制内膜增生,晚期对内皮化进程影响较小。

Objective Fabricating mesoporous silica-rapamycin-heparin drug-eluting stent (MRHES), and then evaluating its biological properties via in vitro and in vivo experiments. Methods The blood compatibility of MRHES was detected by haemolysis test and platelet adhesion test. We implanted MRHES and bare metal stent (BMS) into one of the rabbit carotid arteries respectively. After operation, they were sacrificed to take out specimens. The specimens were divided into two sections: the first segment were hematoxylin-eosin staining after they were sected to observe the intimal hyperplasia, and the second segment were scanned by electron microscopy to observe the endothelialization. Results MRHES had good blood compatibility. After 30 days, the average thickness of the intima was: BMS:(0.14±0.01) mm, MRHES:(0.08±0.01) mm, P<0.01. After 90 days, the average thickness of the intima was: BMS:(0.38±0.04) mm, MRHES:(0.20±0.03) mm, P<0.01. After 30 days, BMS was nearly completely endothelialized, but not MRHES. After 90 days, both of them were completely endothelialized. Conclusion MRHES showed excellent blood compatibility. It inhibited intimal hyperplasia in the early stage, but had little effect on endothelialization lately.