Eldor A, Zylber-Katz E, Levy M
Eur J Clin Pharmacol. 1984;26(2):171-6. doi: 10.1007/BF00630282.
Platelet aggregation and thromboxane A2 (TXA2) production induced by arachidonic acid and collagen were studied in 10 healthy volunteers prior to and at various times after the oral administration of a single dose of 1 g dipyrone. The plasma concentrations of four dipyrone metabolites were also determined. Dipyrone inhibited platelet aggregation and markedly decreased TXA2 synthesis induced by threshold concentrations of both agonists. Maximal inhibition was noted 1 hour after drug administration and in some subjects it lasted as long as 72 h. At all times the effect of the drug could be abolished by increasing the concentration of the agonist. This is consistant with a competitive inhibitory effect of dipyrone on prostaglandin synthetase activity. The mean plasma concentration of the main dipyrone metabolite methylaminoantipyrine at 1 h was 11 micrograms/ml. There was no correlation between individual plasma levels and the parameters of platelet function. At 24h the mean concentration of each of the metabolites studied was up to 1 microgram/ml, and these levels, too, did not correlate with the biological effect of the drug.
在10名健康志愿者口服单剂量1g安乃近之前及之后的不同时间，研究了花生四烯酸和胶原诱导的血小板聚集及血栓素A2（TXA2）生成情况。同时还测定了四种安乃近代谢产物的血浆浓度。安乃近抑制血小板聚集，并显著降低两种激动剂阈浓度诱导的TXA2合成。给药后1小时观察到最大抑制作用，在一些受试者中这种作用持续长达72小时。在所有时间，增加激动剂浓度均可消除药物的作用。这与安乃近对前列腺素合成酶活性的竞争性抑制作用一致。给药后1小时主要安乃近代谢产物甲氨基安替比林的平均血浆浓度为11微克/毫升。个体血浆水平与血小板功能参数之间无相关性。在24小时时，所研究的每种代谢产物的平均浓度高达1微克/毫升，这些浓度也与药物的生物学效应无关。
