Kang I K, Kwon O H, Kim M K, Lee Y M, Sung Y K
Department of Polymer Science, Kyungpook National University, Taegu, Korea.
Biomaterials. 1997 Aug;18(16):1099-107. doi: 10.1016/s0142-9612(97)00035-5.
Blood compatibilities of functional group-grafted and heparin-immobilized polyurethanes (PUs) were investigated using in vitro thrombus formation, plasma recalcification time (PRT), activated partial thromboplastin time (APTT), platelet adhesion and activation, and peripheral blood mononuclear cell (PBMC) activation. In the experiment with plasma proteins, PRT was shortened on amine group-grafted PU (PU-NH2) but prolonged on heparin-immobilized polyurethane (PU-Hep) when compared to PU control. APTT was significantly prolonged on PU-Hep, suggesting the binding of immobilized heparin to antithrombin III. The percentage of platelet adhesion was slightly increased by the introduction of functional groups such as carboxylic acid and primary amine on PU surfaces, but significantly decreased by the immobilization of heparin on the same substrate. The percentage of serotonin released from platelets adhered on surface-modified PUs was increased with increase of platelet adhesion. In the PBMC experiment, cells adhered less on heparin-immobilized PUs than on functional group-grafted PUs, and the production levels of tumour necrosis factor mRNAs from the cells stimulated by heparin-immobilized PU (PU-N-Hep) were smaller than those by the other substrates.
通过体外血栓形成、血浆复钙时间（PRT）、活化部分凝血活酶时间（APTT）、血小板黏附与活化以及外周血单个核细胞（PBMC）活化，研究了官能团接枝和肝素固定化聚氨酯（PU）的血液相容性。在血浆蛋白实验中，与PU对照组相比，胺基接枝PU（PU-NH2）上的PRT缩短，而肝素固定化聚氨酯（PU-Hep）上的PRT延长。PU-Hep上的APTT显著延长，表明固定化肝素与抗凝血酶III结合。PU表面引入羧酸和伯胺等官能团会使血小板黏附百分比略有增加，但在同一底物上固定肝素则会使其显著降低。黏附在表面改性PU上的血小板释放的5-羟色胺百分比随血小板黏附增加而增加。在PBMC实验中，细胞在肝素固定化PU上的黏附少于在官能团接枝PU上的黏附，并且肝素固定化PU（PU-N-Hep）刺激的细胞中肿瘤坏死因子mRNA的产生水平低于其他底物刺激的细胞。
