金属螯合剂对金属酶的影响。

Influence of metal chelators on metalloenzymes.

作者信息

Khandelwal S, Kachru D N, Tandon S K

出版信息

Toxicol Lett. 1987 Aug;37(3):213-9. doi: 10.1016/0378-4274(87)90134-2.

Abstract

The influence of chelating agents (1 mmol/kg/day X 6,i.p.) on trace metal mobilization and activities of certain metalloenzymes was investigated in rats. Calcium disodium ethylenediamine tetraacetate (CaNa2EDTA) and calcium trisodium diethylenetriamine pentaacetate (CaNa3DTPA) enhanced urinary excretion of Zn, while sodium 2,3-dimercaptopropane-1-sulfonate (NaDMPS) and sodium diethyldithiocarbamate (NaDDC) increased that of Cu. The activity of Zn-metalloenzymes-blood delta-aminolevulinic acid dehydratase (delta-ALA-D), plasma alkaline phosphatase (ALP) and that of Cu-metalloenzyme-plasma amine oxidase was decreased as a consequence of chelation therapy. However, hepatic levels of delta-ALA-D, ALP and alcohol dehydrogenase remained unaffected by chelation. The activity of hepatic Fe-metalloenzyme-catalase was increased by polyaminocarboxylic acids and lowered by thiol chelators. The metal chelators decreased the hepatic glutathione levels.

摘要

在大鼠中研究了螯合剂（1 mmol/kg/天×6，腹腔注射）对痕量金属动员及某些金属酶活性的影响。乙二胺四乙酸二钠钙（CaNa2EDTA）和二乙烯三胺五乙酸三钠钙（CaNa3DTPA）增加了锌的尿排泄量，而2,3-二巯基丙烷-1-磺酸钠（NaDMPS）和二乙基二硫代氨基甲酸钠（NaDDC）增加了铜的尿排泄量。螯合疗法导致锌金属酶——血δ-氨基乙酰丙酸脱水酶（δ-ALA-D）、血浆碱性磷酸酶（ALP）以及铜金属酶——血浆胺氧化酶的活性降低。然而，肝脏中δ-ALA-D、ALP和乙醇脱氢酶的水平不受螯合影响。多氨基羧酸使肝脏铁金属酶——过氧化氢酶的活性增加，而硫醇螯合剂使其降低。金属螯合剂降低了肝脏谷胱甘肽水平。