槲皮素硫酸酯对猪血小板胞浆游离钙浓度和蛋白激酶C的影响

槲皮素（ｑｕｅｒｃｅｔｉｎ，Ｑｕｅ），是一种天然的黄酮类化合物，具有多种生物活性［１］，但是Ｑｕｅ水溶性差，口服时胃肠难以吸收［２］．因此，为进一步开发和利用Ｑｕｅ，人工合成水溶性Ｑｕｅ——槲桷皮素硫酸酯（ｓｏｄｉｕｍｑｕｅｒｃｅｔｉｎｓｕｌｆａｔｅ...

Effects of Sodium Quercetin Sulfate on Cytosolic Calcium Concentration and Protein Kinase C in Pig Platelets

Quercetin is a kind of natural flavonoids.Various pharmacological activities of quercetin have been studied extensively.Sodium quercetin sulfate (SQS) has inhibitory effect on platelet aggregation induced by thrombin,but the mechanism of SQS on blood platelet still remains unclear. Effects of SQS on cytosolic calcium concentration ([Ca 2+ ] i) induced by thrombin and protein kinase C(PKC) in pig platelets has been studied.[Ca 2+ ] i was determined by Fura 2 AM fluorescence technique and PKC activity was assayed by incubating PKC with histone ⅢS and [γ 32 P] ATP.The results showed that SQS inhibited Ca 2+ influx in blood platelet induced by thrombin in the presence of extracellular Ca 2+ 1 mmol·L -1 ;SQS also had inhibitory effect on internal Ca 2+ release in the absence of extracellular Ca 2+ .SQS inhibited the activity of cytosolic PKC from blood platelet,but had no effect on membrane PKC.SQS inhibited platelet aggregation induced by thrombin and its molecular mechanism might be due to its inhibition of calcium pathway and PKC pathway.This work primarily provided evidence that helps to clarify the molecular mechanism of the antiplatelet actions of SQS.