ELUCIDATION OF ANTITHROMBOGENIC MECHANISM ON PHEMA-PST-PHEMA ABA TYPE BLOCK COPOYMER SURFACE WITH LAMELLAR SHAPED-MICRODOMAIN STRUCTURE

为了阐明具有片状微区结构的PHEMA-PST-PHEMA-ABA嵌段共聚物表面(HSB)的抗血栓形成机理，用透射电子显微镜分析了附着在HSB表面的血小板膜糖基化(GC)和膜骨架(MS)解离和MS未解离的血小板的超微结构。然后用图像分析仪对MS未分离和MS分离的血小板每1微米^2的储存颗粒数进行定量评估。以PST和PHEMA-PST无规共聚物(HSR)表面为对照。用微球柱法研究了不同流速条件下，血小板与对照聚合物表面的相互作用。血小板膜糖蛋白Ru红染色。用盐酸地布卡因治疗血小板MS解离。HSB表面的血小板与支撑狭窄的空间结合形成支架，保持GC-t-…另一方面，对照聚合物表面的血小板粘附性较好，没有较窄的GC空隙，表明粘附性较强。他们的外部GC似乎在某些地方缺乏。与对照聚合物表面相比，HSB表面未解离的MS血小板的超微结构变化明显受到抑制。HSB表面的血小板储存颗粒的数量与完整的血小板相比没有任何显著差异。另一方面，观察到MS解离的血小板附着在所有对照聚合物表面，形成圆形。血小板储存颗粒的数量在所有聚合物表面和完整的血小板之间没有明显的差异。结果表明，HSB表面的微区结构通过阻止GC向MS传递的跨膜信号而抑制了超微结构的变化，而与不同的流速无关。较少

In order to elucidate the antithrombogenic mechanism on PHEMA-PSt-PHEMA ABA type block copolymer surfaces (HSB) with lamellar shaped-microdomain structure, ultrastructures of platelet membrane glycocalyx (GC) and membrane skeleton (MS) -dissociated and MS-non-dissociated platelets that adhered to the HSB surfaces were analyzed by transmission electron microscopy (TEM). The number of storage granules per 1mum^2 of MS-non-dissociated and MS-dissociated platelets was then evaluated quantitatively by the image processor-analyzer. PSt and PHEMA-PSt random copolymer (HSR) surfaces were used as controls. The interaction of the platelets and the control polymer surfaces was carried out with the microsphere column method under the different flow rate conditions. The platelet GC was stained with ruthenium red. The dissociation of platelet MS was treated with dibucaine hydrochloride. The platelets on the HSB surfaces adhered with supporting narrow spaces which formed scaffolding, keeping the GC t … More he same as the intact platelet GC.On the other hand, the platelets on the control polymer surfaces adhered without the narrow spaces for the GC,indicating strong adhesion. Their external GC seemed to be lacked in some places. The ultrastructural changes of MS-non-dissociated platelets on the HSB surfaces were inhibited significantly compared to that on the control polymer surfaces. The number of the platelet storage granules on the HSB surfaces did not indicate any significant difference compared to those of the intact platelets. On the other hand, the MS-dissociated platelets adhered to all the control polymer surfaces were observed to form round shapes. The number of the platelet storage granules did not indicate any signifficant difference between all the polymer surfaces and the intact platelets. It was suggested that the microdomain structure of the HSB surfaces inhibited the ultrastructural changes by obstructing the transmembrane signaling to the MS from the GC without regard to the different flow rates. Less