电泳纯的LDL的快速提取及Cu^(++)对其氧化修饰的影响

A method of rapid separation of low density lipoprotein and the effect of Cu^(++) on its oxidative modification

本文报道一种快速提取低密度脂蛋白(LDL)及其氧化修饰的方法,获得的LDL可达电泳纯。用CuSO_4催化LDL氧化修饰,其脂质过氧化物(LPO)含量为作用前及用EDTA保护(200mmol/L)的LDL的5倍(P<0.01)。聚丙烯酰胺凝胶电泳可将修饰的LDL与自然LDL予以区别。

A rapid method has been developed for separation and oxidative modification of Low Density Lipoprotein ( LDL ) ; A discontinous NaCl/KBr density gradient was formed by adjusting the density ( d ) of the plasma to 1.30 g/ml with KBr and layering 0.9% NaCl (1.006g/ml ) saline over the adjusted plasma. Tubes loaded with sample were immediately centrifuged at 4 ℃ for 5 hours. The speed was 50,000 r/min. LDL ( 1.006-1.063g/ml ) was separated from other fractions of plasma lipo-protein. It was identified as of electrophoresis purity. LDL was modified by exposed to 5 μmol/L CuSO4, Compared to native LDL, the content of Lpo in LDL exposed to Cu ++ for 6 hours was increased 5-fold. Modified LDL and native LDL can be separated by polyacrylamide disc gel electrophoresis.