Wieslander J B, Dougan P, Stjernquist U, Aberg M, Bergentz S E
Surg Gynecol Obstet. 1986 Sep;163(3):256-62.
Microarterial anastomoses were performed on the central arteries of the ears in rabbits. An untreated control group was compared with two groups treated with saline solution and dextran 70 in saline solution respectively. Anastomotic bleeding times were prolonged in both treated groups. In vivo accumulation of 32phosphorous labelled platelets infused prior to any treatment was measured at the anastomotic sites for two hours after anastomosis. Treatment with saline solution resulted in prolonged periods of platelet accumulation--desaggregation processes and abnormally high levels in 50 per cent of the rabbits. Treatment with dextran resulted in increased quantitative accumulation of platelets at all times compared with the control groups. In some rabbits treated with dextran, platelet accumulation patterns indicated microembolization due to increased platelet thrombus fragility. Despite increased platelet accumulation in the dextran groups all vessels showed good patency and only small amounts of thrombosis material compared with the control and saline solution groups. Poor patency was registered only in one instance in the control group and two instances in the saline solution group. Using ex vivo platelet aggregometry, saline solution slightly decreased and dextran slightly increased platelet aggregability. The conclusion is that dextran does not act as an antiplatelet agent but minimizes formation of dangerous solid fibrin platelet thrombi due to a defective fragile fibrin structure adn perhaps increased fibrinolysis.
在兔耳部的中央动脉上进行微动脉吻合术。将未处理的对照组与分别用盐溶液和盐溶液中右旋糖酐70处理的两组进行比较。两个处理组的吻合口出血时间均延长。在任何处理之前注入的32磷标记血小板在吻合术后两小时在吻合部位的体内蓄积情况被测定。盐溶液处理导致血小板蓄积 - 解聚过程延长，50%的兔体内水平异常高。与对照组相比，右旋糖酐处理导致所有时间点血小板的定量蓄积增加。在一些用右旋糖酐处理的兔中，血小板蓄积模式表明由于血小板血栓脆性增加导致微栓塞。尽管右旋糖酐组血小板蓄积增加，但与对照组和盐溶液组相比，所有血管均显示通畅良好且仅有少量血栓形成物质。对照组仅1例、盐溶液组仅2例记录到通畅不良。使用体外血小板聚集测定法，盐溶液使血小板聚集性略有降低，右旋糖酐使血小板聚集性略有增加。结论是，右旋糖酐并非作为抗血小板剂起作用，而是由于有缺陷的脆弱纤维蛋白结构以及可能增加的纤维蛋白溶解作用，使危险的固体纤维蛋白血小板血栓形成减至最少。
