人胎盘中转铁蛋白受体亲和力与铁转运

Transferrin receptor affinity and iron transport in the human placenta.

作者信息

Brown P J, Molloy C M, Johnson P M

出版信息

Placenta. 1982 Jan-Mar;3(1):21-8. doi: 10.1016/s0143-4004(82)80014-3.

Abstract

Transferrin receptor activity has been investigated on isolated human placental syncytiotrophoblast microvillous plasma membrane preparations following 3 M KCl washing of membranes to remove endogenous receptor-bound maternal transferrin. The calculated binding parameters for essentially apo- and diferric human transferrin, and also for rabbit transferrin, were closely comparable (ranges: Ka, 3.5 to 5.0 X 10(7) M-1; n, 2.6 to 4.0 X 10(14)/mg membrane protein). Iron transport in pregnancy is thus unlikely to involve a simple process of transferrin displacement following iron release at the placental trophoblast plasma membrane receptor site.

摘要

在用3M氯化钾洗涤膜以去除与受体结合的内源性母体转铁蛋白后，对分离出的人胎盘合体滋养层微绒毛质膜制剂的转铁蛋白受体活性进行了研究。计算得出的基本脱铁和双铁人转铁蛋白以及兔转铁蛋白的结合参数非常相近（范围：Ka，3.5至5.0×10⁷ M⁻¹；n，2.6至4.0×10¹⁴/mg膜蛋白）。因此，孕期的铁转运不太可能涉及在胎盘滋养层质膜受体位点铁释放后转铁蛋白置换的简单过程。