Tall A R, Sammett D, Vita G M, Deckelbaum R, Olivecrona T
J Biol Chem. 1984 Aug 10;259(15):9587-94.
These studies were undertaken to examine the effects of lipoprotein lipase (LPL) and cholesteryl ester transfer protein (CETP) on the transfer of cholesteryl esters from high density lipoproteins (HDL) to very low density lipoproteins (VLDL). Human or rat VLDL was incubated with human HDL in the presence of either partially purified CETP, bovine milk LPL or CETP plus LPL. CETP stimulated both isotopic and mass transfer of cholesteryl esters from HDL into VLDL. LPL caused only slight stimulation of cholesteryl ester transfer. However, when CETP and LPL were both present, the transfer of cholesteryl esters from HDL into VLDL remnants was enhanced 2- to 8-fold, compared to the effects of CETP alone. The synergistic effects of CETP and LPL on cholesteryl ester transfer were more pronounced at higher VLDL/HDL ratios and increased with increasing amounts of CETP. In time course studies the stimulation of cholesteryl ester transfer activity occurred during active triglyceride hydrolysis. When lipolysis was inhibited by incubating LPL with either 1 M NaCl or 2 mM diethylparanitrophenyl phosphate, the synergism of CETP and LPL was reduced or abolished, and LPL alone did not stimulate cholesteryl ester transfer. These experiments show that LPL enhances the CETP-mediated transfer of cholesteryl esters from HDL to VLDL. This property of LPL is related to lipolysis.
开展这些研究是为了检验脂蛋白脂肪酶（LPL）和胆固醇酯转运蛋白（CETP）对胆固醇酯从高密度脂蛋白（HDL）向极低密度脂蛋白（VLDL）转移的影响。将人或大鼠的VLDL与人类HDL在部分纯化的CETP、牛乳LPL或CETP加LPL存在的情况下进行孵育。CETP刺激了胆固醇酯从HDL向VLDL的同位素和质量转移。LPL仅引起胆固醇酯转移的轻微刺激。然而，当CETP和LPL都存在时，与单独使用CETP的效果相比，胆固醇酯从HDL向VLDL残粒的转移增强了2至8倍。CETP和LPL对胆固醇酯转移的协同作用在较高的VLDL/HDL比率时更为明显，并随着CETP量的增加而增加。在时间进程研究中，胆固醇酯转移活性的刺激发生在活跃的甘油三酯水解过程中。当通过将LPL与1 M NaCl或2 mM对硝基苯磷酸二乙酯孵育来抑制脂解时，CETP和LPL的协同作用降低或消除，并且单独的LPL不会刺激胆固醇酯转移。这些实验表明，LPL增强了CETP介导的胆固醇酯从HDL向VLDL的转移。LPL的这一特性与脂解有关。
