Identification of albumin as the plasma carrier for zinc absorption by perfused rat intestine.
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.
D000818:Animals; D002352:Carrier Proteins / Q000097:blood*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D066298:In Vitro Techniques; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000378:metabolism; D008297:Male; D010477:Perfusion; D051381:Rats; D012709:Serum Albumin / Q000378:metabolism; D015032:Zinc / Q000378:metabolism*
D002352:Carrier Proteins; D012709:Serum Albumin; D015032:Zinc