title: Cadmium speciation and transport in the blood of the bivalve Mytilus edulis.
abstract: Cadmium (Cd) speciation in the blood plasma of Mytilus edulis was investigated using the metal speciation model MINTEQA2. In the presence of inorganic ions alone, Cd-chloro complexes dominated the speciation (97% of total Cd), with 3% as Cd2+. Inclusion of a novel Cd-binding histidine-rich glycoprotein (HRG) purified from mussel blood plasma decreased the contribution of chloro-complexes to 11.9%, with 86.8% of the Cd bound to the HRG and 1.3% present as Cd2+. Cd transfer from the blood plasma to the kidneys in vivo was studied by injecting 109Cd (both with and without additional chelation) into mussels. Oxine and EDTA complexed a significant amount of blood-borne Cd (23.7% Cd Oxine; 57.1% CdEDTA). In the presence of each chelator, plasma retained significantly more Cd, although there was no significant difference in Cd uptake by tissues (kidney, gill-mantle, and remaining viscera).
authors.affiliation: Environmental, Coastal and Ocean Sciences Department, University of Massachusetts, Boston, 100 Morrissey Boulevard, Boston, MA 02125-3393, USA. g2697pnair@umbsky.cc.umb.edu
authors.forename: P S
authors.initials: PS
authors.lastname: Nair
authors.forename: W E
authors.initials: WE
authors.lastname: Robinson
mesh_terms: D000818:Animals; D001692:Biological Transport; D049872:Bivalvia / Q000378:metabolism*; D002104:Cadmium / Q000097:blood*; D004492:Edetic Acid / Q000378:metabolism; D007668:Kidney / Q000378:metabolism; D015125:Oxyquinoline / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D000099053:Histidine-Rich Glycoprotein
chemical_list: D011506:Proteins; D000099053:Histidine-Rich Glycoprotein; D002104:Cadmium; D015125:Oxyquinoline; D004492:Edetic Acid