Young S P, Aisen P
Hepatology. 1981 Mar-Apr;1(2):114-9. doi: 10.1002/hep.1840010205.
Isolated rat hepatocytes accumulate iron from iron-transferrin by a process which is dependent on the temperature and on the transferrin concentration, and which is diminished by treatment of the cells with a proteolytic enzyme. These observations are consistent with a mechanism for iron uptake into hepatocytes involving the binding of iron-transferrin to a specific cell-surface receptor. Apotransferrin is also able to bind to the hepatocyte but the apparent binding constant is about 35 times lower than that observed for the binding of iron-transferrin. The binding of apotransferrin to the cells is completely abolished by a low concentration of iron-transferrin. This suggests that the apotransferrin is binding weakly to the same receptor to which iron-transferrin binds and that there are not receptors on the surface of the hepatocyte specific for apotransferrin. In the absence of such specific-binding sites, apotransferrin may act as a passive acceptor of iron released from the hepatocyte.
分离的大鼠肝细胞通过一个依赖于温度和转铁蛋白浓度的过程从转铁蛋白中积累铁，并且用蛋白水解酶处理细胞会减少该过程。这些观察结果与铁摄取进入肝细胞的机制一致，该机制涉及铁转铁蛋白与特定细胞表面受体的结合。脱铁转铁蛋白也能够与肝细胞结合，但表观结合常数比观察到的铁转铁蛋白结合常数低约35倍。低浓度的铁转铁蛋白会完全消除脱铁转铁蛋白与细胞的结合。这表明脱铁转铁蛋白与铁转铁蛋白结合的是同一个受体，只是结合较弱，并且肝细胞表面不存在脱铁转铁蛋白特异性受体。在没有这种特异性结合位点的情况下，脱铁转铁蛋白可能作为从肝细胞释放的铁的被动受体。
