Goldenberg H, Eder M, Pumm R, Wallner E, Retzek H, Hüttinger M
Department of Medical Chemistry, University of Vienna, Austria.
Biochim Biophys Acta. 1988 Mar 11;968(3):331-9. doi: 10.1016/0167-4889(88)90024-9.
Radioactively labelled transferrin was injected into rats intravenously and its uptake and subcellular distribution in the liver was investigated. The amount of radioactivity in the liver remained constant from 10 min after injection. It was not influenced by asialoglycoproteins. The radioactive label was identified as asialotransferrin. After subcellular fractionation by differential and zonal sucrose density-gradient centrifugation the label was enriched in a low-density endocytic compartment showing fluorescence quenching of acridine orange and N-ethylmaleimide-sensitive ATPase activity. The data fit into a model of continuous transferrin-receptor-mediated recycling through the hepatocyte's endocytic compartment.
将放射性标记的转铁蛋白静脉注射到大鼠体内，研究其在肝脏中的摄取及亚细胞分布。注射后10分钟起，肝脏中的放射性量保持恒定。它不受去唾液酸糖蛋白的影响。放射性标记物被鉴定为去唾液酸转铁蛋白。通过差速和区带蔗糖密度梯度离心进行亚细胞分级分离后，标记物在一个低密度内吞区室中富集，该区域显示吖啶橙荧光猝灭和对N-乙基马来酰亚胺敏感的ATP酶活性。这些数据符合转铁蛋白受体介导的通过肝细胞内吞区室进行连续循环的模型。
