脂蛋白（a）及低密度脂蛋白与成纤维细胞表面结合特性的比较

脂蛋白（a)[Lipoprotein(a),Lp(a)]的代谢途径尚有争议。本文比较研究了Lp(a)和低密度脂蛋白（Low Density Lipoprotein,LDL)与成纤维细胞表面的结合特性,结果显示,Lp(a)与成纤维细胞呈特异性,高亲和力,可饱和性结合,但是Lp(a)与细胞的亲和力,最大结合容量均比LDL低,竞争性结合试验显示LDL只能部分抑制Lp(a)与成纤维细胞表面特异性的结合;细胞表面LDL受体活性的下调,可使LDL与细胞的结合量下降58％,而Lp(a)的结合量仅下降12．3％,这些结果表明LDL受体只能参与部分Lp(a)与细胞表面的结合及代谢。

Binding of Lp(a) by the Fibroblast: A Comparison with LDL

Lipoprotein(a) is a high atherogenic lipoprotein, but there is no convincing finding to prove the Lp(a) catabolic pathway In this paper, Binding susceptibility of Lp(a) with the human embryonic lung fibroblast compared with that of LDL was studied. the results realed that Lp(a) was bound with speciality,high affinity,saturation by the fibroblasts surface, but the maximum binding capacity and the affinity of Lp(a) were lower than those of LDL;The competition binding experiments indicated that LDL failed completely inhibit special binding of Lp(a) by the fibroblasts surface The down regulation of LDL receptor activity on HELF induced that the binding capatity of LDL decreased by 58% and that of Lp(a) only decreased by 12 3% The results suggested that binding of Lp(a) was not only mediated by the LDL receptor pathway but also by other receptors or non receptor mediated pathways