毛冬青甲素和硝酸甘油对花生四烯酸代谢的影响

本文主要研究了毛冬青甲素在体外及体内对活化血小板功能途径的二磷酸腺苷(ADP)诱导的血小板聚集的抑制作用及与前列环素(PGI_2)样物质的作用。提示毛冬青甲素在体内能抑制活化血小板功能途径的花生四烯酸(AA),同时在体内及体外能抑制ADP活化血小板功能的途径。采用放射免疫法测定了兔血浆中血小析噁A_2(TXA_2)和PGI_2代谢物TXB_2及6—keto—PGF_(1α)的水平。结果提示毛冬青甲素可能主要是通过促进动脉内皮生成前列环素,而产生其抗血栓作用的。

Effects of Ilexonin A and Nitroglycerin on Arachidonic Acid Metabolism

The inhibitory effect of ilexonin A(IA)on platelet aggregation in vitro and in vivo induced By adengsine diphosphate(ADP)whichactivates platelet function was studied in this paper.The effect of IA onprostacyclinlike substances was also investigated.Basing on in vivostudy,our result suggested that IA was an inhibitor of arachidonicacid(AA)which activated platelet function in another way.Meanwhile,IA inhibited the way by which ADP activated platelet function in vitroand in vivo.In further study with radioimmunassay,we measured theplasma levels of thromboxane B₂(TXB₂)and 6-keto-PGF₁ in rabbit.Theantithrombotic agent might be caused through the stimulation action ofIA of prostacyclin production from arterial endothelium in vivo.In vitroand in vivo experiments showed that nitroglycerin(NTG)had inhibitoryeffects both on ADP and AA.It also enhanced the inhibitory effect ofPGI₂-like substances on platelet aggregation.It was suggested that NTGexerted its regulating effect on TXA₂/PGI₂ balance.In the acutely lethalexperiment,both IA and NTG had apparent protective effects.