老年大鼠血小板反应性及血小板膜LDL受体活性的改变

CHANGES OF PLATELET REACTIVITY AND LDL RECEPTOR ACTIVITY IN ELDERLY RATS

本文利用受体放射配基分析方法观察不同年龄大鼠血小板聚集性、血浆脂质水平及血小板膜LDL受体活性的改变。结果表明,老年大鼠血小板对ADP诱导的聚集反应性明显增强;血浆总胆固醇、低密度脂蛋白胆固醇水平增高;血小板膜LDL受体活性增强,解离常数显著低于对照组。本文作者认为血小板膜受体活性的增强及血浆LDL水平的增高可促进LDL与血小板的结合,提高了LDL对血小板功能的影响,与老年大鼠血小板高反应性改变可能有关。

Enhancement of platelet reactivity may bring about platelet adhesion, aggregation, and formation of thrombi at the damaged vessel wall where many biologically active substances were released. Platelet hyper-reaotivity has been thought to be an important pathophysiological bases of Some cardiovascular diseases. In the present study, platelet aggregation, plasma lipid concentration and LDL receptor activity in platelet membrane were studied in rata of different ages. The results indicated that ADP-induced platelet aggregation, plasma total cholesterol, LDL-cholesterol levels and LDL receptor affinity were increased in the elderly rats. It is suggested that increased LDL receptor activity and LDL levels may enhance the binding of LDL with platelets and the effect of LDL on platelet function, and be pertinent to platelet high-reactivity in elderly rats.