流动条件下血栓通胶囊抗血小板黏附的分子药理学机制研究

Anti-platelet adhesive effect and mechanisms of Xueshuantong capsules under flow conditions

研究流动条件下血栓通胶囊(XST)抗血小板黏附的效应及其可能的作用机制。利用Bio Flux 1000控剪应力微流培养系统模拟体内流动条件,建立TNF-α诱导的血管内皮细胞损伤模型,动态实时观察XST(0.3 g·L-1)对血小板黏附于受损血管内皮细胞表面的影响。以Western blotting法测定血管内皮细胞VCAM-1的表达,以放射免疫法检测6-keto-PGF1α,TXB2的分泌。结果显示,生理和病理流动条件下XST均可抑制血小板黏附,抑制率分别为15.0%,34.1%;在病理低剪应力或静态条件下,XST能够明显抑制血管内皮细胞VCAM-1的表达和TXB2释放(P<0.05)。该研究从血流/血管/血液相互作用的角度发现,XST可能通过内皮细胞保护途径,抑制血小板黏附,进而发挥其抗血栓形成的效应。在不同流动条件下,XST抗血小板黏附的效应有所不同,病理低剪应力更有利于XST药效的发挥。

To investigate the anti-platelet adhesive effect and possible mechanisms of Xueshuantong capsule（XST） under flow conditions. Human umbilical vein endothelial cells（ HUVECs） and human platelets were employed as experimental materials,and TNF-α（20μg·L- 1） was used to establish vascular endothelial cell injury models. In vivo flow conditions were simulated under controlled shear stress of 0. 1 Pa and 0. 9 Pa by Bioflux1000 assays accordingly. Anti-platelet adhesive effects of XST at 0. 3 g·L-1were dynamically monitored by microscopic time-lapse photography. Western blotting was employed to detect the VCAM-1 expression on endothelial cells,and the release of 6-keto-PGF1 αand TXB2 was tested by radioimmunoassay. The results showed that XST could inhibit the platelets adhesion under both physiological and pathological flow conditions,and the inhibition rate was 15. 0% and 34. 1% respectively. Under pathological low shear stress or static conditions,XST could significantly inhibit endothelial cells VCAM-1 expression and TXB2release（ P 〈 0. 05）.These results suggested that XST inhibited platelets adhering to injured endothelium via decreasing VCAM-1 expression and TXA2 secretion from endothelium. From the interactions among blood flow,vascular endothelium and platelets,the anti-thrombosis effects of XST were possibly related to endothelial cells protection and therefore inhibiting platelets adhesion. Under different flow conditions,the antiplatelet adhesion effect of XST was different,and the pathological low shear stress was more conducive to the efficacy of XST.