Ranganathan S, Kottke B A
Atherosclerosis Research Unit, Mayo Clinic and Foundation, Rochester, MN 55905.
Biochim Biophys Acta. 1990 Sep 18;1046(2):223-8. doi: 10.1016/0005-2760(90)90193-2.
The effect of fetal bovine serum (FBS) on the secretion of apolipoprotein A-I (apo A-I) by HepG2 cells was studied. The cells incubated with FBS always secreted more apo A-I than the cells incubated with serum-free medium. The changes in the rate of apo A-I secretion were observed within 1 h after addition or depletion of serum. The high-density lipoproteins (HDL) or the lipoprotein-deficient serum (LPDS) obtained from FBS also stimulated apo A-I secretion rapidly to the same level as obtained with FBS. Addition of low-density lipoproteins did not have any effect. The rate of general protein synthesis was not affected by short-term incubations with or without serum or HDL. The rate of apolipoprotein E secretion by these cells did not change significantly, parallel to the changes in apo A-I secretion in the presence or absence of FBS. It is concluded that serum may have a factor that plays a specific role in the regulation of apo A-I secretion by the liver cells and this factor is associated with the HDL fraction.
研究了胎牛血清（FBS）对HepG2细胞载脂蛋白A-I（apo A-I）分泌的影响。与含FBS孵育的细胞总是比与无血清培养基孵育的细胞分泌更多的apo A-I。在添加或去除血清后1小时内观察到apo A-I分泌速率的变化。从FBS获得的高密度脂蛋白（HDL）或脂蛋白缺陷血清（LPDS）也能迅速刺激apo A-I分泌至与FBS相同的水平。添加低密度脂蛋白没有任何影响。短期孵育有无血清或HDL对总蛋白合成速率没有影响。这些细胞载脂蛋白E的分泌速率没有明显变化，与有无FBS时apo A-I分泌的变化平行。得出的结论是，血清可能有一种在肝细胞apo A-I分泌调节中起特定作用的因子，并且该因子与HDL部分相关。
