Bier D M, Havel R J
J Lipid Res. 1970 Nov;11(6):565-70.
Triglycerides in fat emulsions are hydrolyzed by lipoprotein lipase only when they are "activated" by serum lipoproteins. The contribution of different lipoprotein fractions to hydrolysis of triglycerides in soybean oil emulsion was assessed by determining the quantity of lipoprotein fraction required to give half-maximal hydrolysis. Most of the activator property of whole serum from normolipidemic, postabsorptive subjects was in high density lipoproteins. Low density lipoproteins and serum from which all lipoprotein classes were removed had little or no activity. Also, little activator was present in guinea pig serum or in very low density poor serum from an individual with lecithin:cholesterol acyltransferase deficiency, both of which are deficient in high density lipoproteins. Human very low density lipoproteins are potent activators and are much more active than predicted from their content of high density lipoprotein-protein. Per unit weight of protein, very low density lipoproteins had 13 times the activity of high density lipoproteins. These observations suggest that one or more of the major apoproteins of very low density lipoproteins, present as a minor constituent of high density lipoproteins, may be required for the activation process.
脂肪乳剂中的甘油三酯只有在被血清脂蛋白“激活”后，才能被脂蛋白脂肪酶水解。通过测定产生半数最大水解所需的脂蛋白组分数量，评估了不同脂蛋白组分对大豆油乳剂中甘油三酯水解的作用。正常血脂、吸收后受试者的全血清的大部分激活特性存在于高密度脂蛋白中。低密度脂蛋白以及去除了所有脂蛋白类别的血清几乎没有或没有活性。此外，豚鼠血清或来自卵磷脂：胆固醇酰基转移酶缺乏个体的极低密度脂蛋白缺乏血清中几乎没有激活剂，这两种血清都缺乏高密度脂蛋白。人极低密度脂蛋白是有效的激活剂，其活性比根据其高密度脂蛋白-蛋白含量预测的要高得多。每单位重量的蛋白质，极低密度脂蛋白的活性是高密度脂蛋白的13倍。这些观察结果表明，激活过程可能需要极低密度脂蛋白的一种或多种主要载脂蛋白，它们作为高密度脂蛋白的次要成分存在。
