title: Chronic Cadmium Exposure Lead to Inhibition of Serum and Hepatic Alkaline Phosphatase Activity in Wistar Rats.
abstract: Alkaline phosphatase (ALP) activity in the serum and liver from rats administered with cadmium (Cd) in drinking water was studied. After metal administration, Cd showed a time-dependent accumulation in the liver, meanwhile metallothionein had a maximum increase at 1 month, remaining in this level until the end of the study. On the other hand, serum and liver ALP activity was decreased after 3 months exposure. To determine if Cd produced an inhibition on enzyme, apo-ALP prepared from both nonexposed and exposed rats was reactivated with Zn, showing 60% more activity as compared with the enzyme isolated from nonexposed rats. In vitro assays showed that Cd-ALP was partially reactivated with Zn; however, in the presence of cadmium, Zn-ALP was completely inhibited. Kinetic studies indicate a noncompetitive inhibition by Cd; these results suggest that Cd can substitute Zn, and/or Cd can interact with nucleophilic ligands essential for the enzymatic activity.
authors.affiliation: Laboratorio de Investigaciones Químico Clínicas, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, México. eduardobrambila1@yahoo.com.mx.
authors.forename: Samuel
authors.initials: S
authors.lastname: Treviño
authors.affiliation: Laboratorio de Investigaciones Químico Clínicas, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, México.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Andrade-García
authors.affiliation: Área de Bioquímica y Biología Molecular, Instituto de Ciencias de la Benemérita Universidad Autónoma de Puebla, México.
authors.forename: Irma
authors.initials: I
authors.lastname: Herrera Camacho
authors.affiliation: Laboratorio de Investigaciones Químico Clínicas, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, México.
authors.forename: Bertha Alicia
authors.initials: BA
authors.lastname: León-Chavez
authors.affiliation: Laboratorio de Investigaciones Químico Clínicas, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, México.
authors.forename: Patricia
authors.initials: P
authors.lastname: Aguilar-Alonso
authors.affiliation: Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, México.|Departamento de Inorgánica, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, México.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Flores
authors.affiliation: Laboratorio de Investigaciones Químico Clínicas, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, México.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Brambila
mesh_terms: D000469:Alkaline Phosphatase / Q000037:antagonists & inhibitors / Q000097:blood / Q000378:metabolism*; D000818:Animals; D001667:Binding, Competitive; D002104:Cadmium / Q000378:metabolism / Q000633:toxicity*; D007700:Kinetics; D008099:Liver / Q000187:drug effects* / Q000201:enzymology; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D015032:Zinc / Q000378:metabolism
chemical_list: D002104:Cadmium; D000469:Alkaline Phosphatase; D015032:Zinc
keywords: Alkaline Phosphatase; Cadmium; Enzymatic Inhibition