Smith K T, Failla M L, Cousins R J
Biochem J. 1979 Dec 15;184(3):627-33. doi: 10.1042/bj1840627.
The isolated vascularly perfused rat intestine exhibits an obligatory need for a protein carrier in order to absorb zinc. Therefore this system is ideal for use as a model to identify the plasma carrier during zinc absorption. Affinity chromatography on Blue Sepharose CL-6B was employed to separate the major serum zinc-binding proteins in the portal effluent of the perfused intestine. It was found that 94% of newly absorbed 65Zn was transported in the portal serum-containing perfusate as an albumin-65Zn complex. The identity of albumin as the plasma carrier was confirmed by polyacrylamide-slab-gel electrophoresis. This evidence suggests that albumin is the plasma protein that is involved in removal of zinc from intestinal-mucosal cells and subsequent transport of the metal in portal blood to the liver.
离体血管灌注大鼠肠道在吸收锌时对蛋白质载体有绝对需求。因此，该系统是用于识别锌吸收过程中血浆载体的理想模型。采用Blue Sepharose CL - 6B亲和层析法分离灌注肠道门静脉流出液中的主要血清锌结合蛋白。结果发现，新吸收的65Zn中有94%在含门静脉血清的灌注液中作为白蛋白 - 65Zn复合物运输。通过聚丙烯酰胺平板凝胶电泳证实白蛋白作为血浆载体的身份。这一证据表明，白蛋白是参与从肠黏膜细胞去除锌并随后将该金属在门静脉血中运输至肝脏的血浆蛋白。
