溶血性磷脂酰胆碱诱导血小板活化及蛋白质酪氨酸激酶和蛋白激酶C的作用  

Lysophosphatidylcholine induced platelet activation and the role of protein tyrosine kinase and protein kinase C

作　　者：杨丹[1,2] 曾珊[1,2] 刘文兰[1,2] 郭兆贵 

机构地区：[1]湖南医科大学分子药理学研究室 [2]中山医科大学生理学教研室

出　　处：《中国药理学与毒理学杂志》1999年第1期49-52,共4页Chinese Journal of Pharmacology and Toxicology

摘　　要：应用双道血小板聚集仪和荧光分光光度计分别测定溶血性磷脂酰胆碱（ＬｙｓｏＰＣ）诱导的兔洗涤血小板聚集，细胞内钙离子浓度（［Ｃａ２＋］ｉ），细胞内ｐＨ值（ｐＨｉ）的变化及５－羟色胺（５－ＨＴ）的释放，并观察蛋白质酪氨酸激酶（ＰＴＫ）抑制剂金雀异黄素（Ｇｅｎ）和蛋白激酶Ｃ（ＰＫＣ）抑制剂星形孢菌素（Ｓｔａ）对其作用的影响．结果表明：ＬｙｓｏＰＣ（３０－３００μｍｏｌ·Ｌ－１）诱导血小板聚集，５－ＨＴ释放和［Ｃａ２＋］ｉ升高，均呈现良好的浓度依赖性，１００μｍｏｌ·Ｌ－１以上时伴有ｐＨｉ的增加；Ｇｅｎ使ＬｙｓｏＰＣ诱导的聚集浓度效应曲线右移，半效聚集浓度值从（１００±２３）μｍｏｌ·Ｌ－１增加到（２００±４２）μｍｏｌ·Ｌ－１，明显抑制［Ｃａ２＋］ｉ升高和胞浆碱化，对５－ＨＴ释放无明显影响；Ｓｔａ对较低浓度ＬｙｓｏＰＣ诱导的血小板聚集，５－ＨＴ释放，［Ｃａ２＋］ｉ和ｐＨｉ的增加均有明显抑制作用，但对高浓度ＬｙｓｏＰＣ诱导的血小板活化无明显影响．提示：ＬｙｓｏＰＣ通过内Ｃａ２＋调节和Ｎａ＋／Ｈ＋交换介导血小板聚集和致密颗粒释放；ＰＴＫ的激活参与了ＬｙｓｏＰＣ诱导的血小板聚集，内Ｃａ２＋调节和Ｎａ＋／Ｈ＋交换，而在５－?A dual channel aggregator and a dual wavelength fluorophotometer were used to measure platelet aggregation, 5 HT release, cytosolic calcium([Ca 2+ ] i)and cytosolic pH(pH i)in washed rabbit platelets induced by lysophosphatidylcholine(LysoPC) and to observe effects of protein tyrosine kinase(PTK) inhibitor genistein(Gen) and protein kinase C(PKC) inhibitor staurosporine(Sta) on these events. The results showed that LysoPC (30-300 μmol·L 1 ) induced platelet aggregation, 5 HT release and [Ca 2+ ] i increase in a concentration dependent manner, concomitant with pH i increase at concentrations above 100 μmol·L 1 . Pretreatment of platelets with Gen produced a rightward shift of the aggregation concentration response curve, AC 50 value increased from (100±23) μmol·L 1 to (200±42) μmol·L 1 . This shift was associated with reductions in △[Ca 2+ ] i and △pH i evoked by LysoPC, but no significant effect on 5 HT release. Sta showed significant inhibitory effects on platelet aggregation, 5 HT release and shifts in [Ca 2+ ] i and pH i induced by LysoPC at lower concentrations, but no effect on high concentration LysoPC stimulated platelet activation. These results indicated that LysoPC induced platelet aggregation and dense granule release via intracellular calcium mobilization and Na +/H + exchanger activation. The activation of PTK is involved in LysoPC stimulated aggregation, calcium mobilization and Na +/H + exchange in platelet. However, the 5 HT release is not related to PTK activation. PKC also plays an important role in platelet activation induced by LysoPC at lower concentrations. Another PKC independent pathway might exist to mediate the action of high concentrations of LysoPC.

关 键 词：溶血磷脂酰胆碱 血小板活化 蛋白激酶C PTK 

分 类 号：R972.6[医药卫生—药品]