载脂蛋白A－Ⅳ和实验性高脂血症时平滑肌细胞内的胆固醇转运

Apolipoprotein A-Ⅳ and transportation of cholesterol from smooth muscle cells in experimental hyperlipidemia

通过建立高胆固醇血症兔模型，观察载脂蛋白（ａｐｏ）Ａ－Ⅳ和ａｐｏＡ－Ⅳ／卵磷脂（ＰＣ）脂质体等对高胆固醇血症兔主动脉平滑肌细胞（ＳＭＣ）内胆固醇的清除及对血清卵磷脂胆固醇酰基转移酶（ＬＣＡＴ）的激活作用。结果显示，ａｐｏＡ－Ⅳ／ＰＣ脂质体清除ＳＭＣ内胆固醇及激活ＬＣＡＴ的能力与ａｐｏＡ－Ⅰ／ＰＣ脂质体、高密度脂蛋白（ＨＤＬ）相似。提示，ａｐｏＡ－Ⅳ与ａｐｏＡ－Ⅰ一样，在胆固醇逆向转运过程中起重要作用；ａｐｏＡ－Ⅳ与ＰＣ人工合成的脂质体有可能代替天然ＨＤＬ而发挥防治动脉粥样硬化的作用。

he effects of apolipoprotein(apo)A-Ⅳ and apoA-Ⅳ/phosphatidylcholine(PC)liposome on cholesterol efflux from the smooth muscle cells originating from the aorta of hypercholesterolemic rabbit model and control rabbits,and on the activation of lecithin cholesterol acyltransferase ( LCAT)were studied respectively, Both apoA-Ⅳ/PC and apoA-Ⅰ/PC liposomes have similar efficiency as the HDL’s,i.e. a strong ability to clear intracellular cholesterol and the ability to activate LCAT. There were no differences noticed on the clearance ability between apoA-Ⅳ and apoA-Ⅰ or between apoA-Ⅳ/PC and apoA-Ⅰ/PC liposomes. These results suggest that apoA-Ⅳ may play an important role in the process of reverse cholesterol transport and apoA-Ⅳ/PC liposome may be effectively used instead of natural HDL to prevent the development of atherosclerosis.