Tohgi H, Takahashi H, Watanabe K, Kuki H, Shirasawa Y
Iwate Medical University, Department of Neurology, Morioka, Japan.
Thromb Haemost. 1996 May;75(5):838-43.
Particle-counting methods that employ light scattering (LS) quantify changes in the number of platelet aggregates of different sizes after the application of an aggregating stimulus. Using the LS method, we studied the effects of aggregant concentration, aspirin administration, and ticlopidine administration on aggregate formation and compared the results with those obtained using the conventional optical density (OD) method. Subjects were 47 controls, 31 patients treated with aspirin (330 mg/day), and 37 patients treated with ticlopidine (200 mg/day). Platelet aggregation after stimulation by 0.5, 1.0 or 5.0 muM ADP, or 0.5, 1.0 or 2.0 micrograms/ml collagen was determined using both methods. Using the LS method, small (9-25 micrograms), medium (25-50 micrograms), and large (50-70 micrograms) aggregates were counted. In patients untreated with antiplatelet medication, greater concentrations of ADP or collagen generated larger aggregates. Generation of small and medium-sized aggregates showed a significant positive correlation with OD levels after stimulation with 0.5 or 1.0 muM ADP, or 0.5 or 1.0 micrograms/ml collagen. In patients treated with aspirin, the development of small aggregates into large aggregates was inhibited. Thus, the number of small aggregates increased. Inhibition induced by aspirin was more effective against aggregation after stimulation with collagen than with ADP. In patients treated with ticlopidine, small and medium-sized aggregate formation was inhibited after stimulation with low concentrations of ADP or collagen, but was promoted after stimulation with high aggregant concentrations. The capability of the LS method to quantify different sizes of aggregates after stimulation with low concentration agonists may facilitate investigation of the aggregation process, and of how this process is affected by antiplatelet agents.
采用光散射（LS）的颗粒计数方法可量化施加聚集刺激后不同大小血小板聚集体数量的变化。我们使用LS方法研究了聚集剂浓度、阿司匹林给药和噻氯匹定给药对聚集体形成的影响，并将结果与使用传统光密度（OD）方法获得的结果进行了比较。受试者包括47名对照组、31名接受阿司匹林治疗（330毫克/天）的患者和37名接受噻氯匹定治疗（200毫克/天）的患者。使用这两种方法测定了0.5、1.0或5.0微摩尔/升二磷酸腺苷（ADP）或0.5、1.0或2.0微克/毫升胶原蛋白刺激后的血小板聚集情况。使用LS方法对小（9 - 25微克）、中（25 - 50微克）和大（50 - 70微克）聚集体进行计数。在未接受抗血小板药物治疗的患者中，更高浓度的ADP或胶原蛋白会产生更大的聚集体。在用0.5或1.0微摩尔/升ADP或0.5或1.0微克/毫升胶原蛋白刺激后，小和中等大小聚集体的生成与OD水平呈显著正相关。在接受阿司匹林治疗的患者中，小聚集体向大聚集体的发展受到抑制。因此，小聚集体的数量增加。阿司匹林诱导的抑制作用对胶原蛋白刺激后的聚集比对ADP刺激后的聚集更有效。在接受噻氯匹定治疗的患者中，低浓度ADP或胶原蛋白刺激后小和中等大小聚集体的形成受到抑制，但高浓度聚集剂刺激后则会促进。LS方法在低浓度激动剂刺激后量化不同大小聚集体的能力可能有助于研究聚集过程以及该过程如何受到抗血小板药物的影响。
