Apitz-Castro R, Cabrera S, Cruz M R, Ledezma E, Jain M K
Thromb Res. 1983 Oct 15;32(2):155-69. doi: 10.1016/0049-3848(83)90027-0.
We studied the effect of the methanol extract of garlic bulbs (EOG) and of three pure components isolated from it (F1, F2, F3), on human platelet aggregation induced by ADP, epinephrine, collagen, thrombin, arachidonate, PAF, and the ionophore A-23187. Incubation of PRP with EOG, either in methanol or in homologous PPP, inhibits platelet aggregation induced by all of the above mentioned agonists. F1, F2, and F3 also inhibit platelet aggregation, however, F3 was about four times more potent. Addition of EOG or F3 to platelets that have already been irreversibly aggregated by 10 microM ADP, induces rapid deaggregation. Inhibition of aggregation was still present after three hours. The inhibitory effect persisted even after the treated platelets were Gel-Filtered (GFP) or separated from plasma through a metrizamide gradient and resuspended in new homologous PPP. Thrombin-induced release of ATP from GFP was inhibited by 75-80% after EOG or F3 treatment. Incorporation of [3-H]-arachidonate by intact platelets was decreased by 50-60% in treated platelets. However, platelets incubated with the inhibitors after incorporation of radiolabeled arachidonate, although did not aggregate, produced, after thrombin activation similar amounts of radiolabeled TXB2 and lipoxygenase products as the controls. Electron microscopy of inhibited platelets, in the presence of thrombin, showed no degranulation but an increase of spherical forms. Our results suggest that the effects described might be mediate by a perturbation of the physicochemical properties of the plasma membrane rather than by affecting arachidonate or calcium metabolism in the cells. Chemical structures of F1, F2 and F3 have been provisionally assigned: F1 is diallytrisulfide, F2 is 2-vinyl-1,3-dithiene, and F3 is most probably allyl 1,5-hexadienyltrisulfide.
我们研究了大蒜鳞茎甲醇提取物（EOG）及其分离出的三种纯成分（F1、F2、F3）对二磷酸腺苷（ADP）、肾上腺素、胶原蛋白、凝血酶、花生四烯酸、血小板活化因子（PAF）和离子载体A - 23187诱导的人血小板聚集的影响。将富血小板血浆（PRP）与甲醇中的EOG或同源血小板贫乏血浆（PPP）一起孵育，可抑制上述所有激动剂诱导的血小板聚集。F1、F2和F3也能抑制血小板聚集，然而，F3的效力约为其他两者的四倍。将EOG或F3添加到已被10微摩尔ADP不可逆聚集的血小板中，可诱导快速解聚。聚集抑制在三小时后仍然存在。即使将处理过的血小板进行凝胶过滤（GFP）或通过甲泛葡胺梯度与血浆分离并重新悬浮于新的同源PPP中，抑制作用依然持续。EOG或F3处理后，凝血酶诱导的GFP中ATP释放被抑制75 - 80%。处理过的血小板中完整血小板对[3 - H] - 花生四烯酸的摄取减少了50 - 60%。然而，在掺入放射性标记的花生四烯酸后用抑制剂孵育的血小板，尽管没有聚集，但在凝血酶激活后产生的放射性标记血栓素B2（TXB2）和脂氧合酶产物的量与对照组相似。在凝血酶存在下对受抑制血小板进行电子显微镜检查，未显示脱颗粒现象，但球形形态增加。我们的结果表明，所描述的这些作用可能是通过扰乱质膜的物理化学性质介导的，而不是通过影响细胞中的花生四烯酸或钙代谢。F1、F2和F3的化学结构已初步确定：F1是二烯丙基三硫化物，F2是2 - 乙烯基 - 1,3 - 二硫烯，F3很可能是烯丙基1,5 - 己二烯基三硫化物。
