title: Computer simulation of Zn(II) speciation and effect of Gd(III) on Zn(II) speciation in human blood plasma.
abstract: The speciation and distribution of Zn(II) and the effect of Gd(III) on Zn(II) speciation in human blood plasma were studied by computer simulation. The results show that, in normal blood plasma, the most predominant species of Zn(II) are [Zn(HSA)] (58.2%), [Zn(IgG)](20.1%), [Zn(Tf)] (10.4%), ternary complexes of [Zn(Cit)(Cys)] (6.6%) and of [Zn(Cys)(His)H] (1.6%), and the binary complex of [Zn(Cys)2H] (1.2%). When zinc is deficient, the distribution of Zn(II) species is similar to that in normal blood plasma. Then, the distribution changes with increasing zinc(II) total concentration. Overloading Zn(II) is initially mainly bound to human serum albumin (HSA). As the available amount of HSA is exceeded, phosphate metal and carbonate metal species are established. Gd(III) entering human blood plasma predominantly competes for phosphate and carbonate to form precipitate species. However, Zn(II) complexes with phosphate and carbonate are negligible in normal blood plasma, so Gd(III) only have a little effect on zinc(II) species in human blood plasma at a concentration above 1.0 x 10(-4) M.
authors.affiliation: Key Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, People's Republic of China.
authors.forename: Jinping
authors.initials: J
authors.lastname: Wang
authors.forename: Haiyuan
authors.initials: H
authors.lastname: Zhang
authors.forename: Kuiyue
authors.initials: K
authors.lastname: Yang
authors.forename: Chunji
authors.initials: C
authors.lastname: Niu
authors.forename: Jiazuan
authors.initials: J
authors.lastname: Ni
mesh_terms: D003198:Computer Simulation; D005682:Gadolinium / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D008024:Ligands; D008954:Models, Biological; D008956:Models, Chemical; D010949:Plasma / Q000737:chemistry* / Q000187:drug effects*; D012709:Serum Albumin / Q000737:chemistry; D015032:Zinc / Q000097:blood* / Q000737:chemistry*
chemical_list: D008024:Ligands; D012709:Serum Albumin; D005682:Gadolinium; D015032:Zinc