Neurochemical Research

, Volume 28, Issue 12, pp 1859–1865 | Cite as

Interaction Between Metals and Chelating Agents Affects Glutamate Binding on Brain Synaptic Membranes

  • Félix Antunes Soares
  • Marcelo Farina
  • Francielli Weber Santos
  • Diogo Souza
  • João Batista Teixeira Rocha
  • Cristina Wayne Nogueira


The present study investigates the possible effects of Hg2+, Pb2+, and Cd2+ on [3H]-glutamate binding. To better understand the role of the thiol-disulfide status on the toxicity of such metals toward glutamatergic neurotransmission, we used three thiol chelating agents, 2,3-dimercaptopropanol (BAL), 2,3-dimercaptopropane 1-sulfonate (DMPS), and meso-2,3-dimercaptosuccinic acid (DMSA). Dithiotreitol (DTT) was tested for its ability to prevent metals-induced inhibition on [3H]-glutamate binding. Hg2+, Pb2+, and Cd2+ showed a concentration-dependent inhibition on [3H]-glutamate binding, and mercury was the most effective inhibitor. BAL did not prevent [3H]-glutamate binding inhibition by Hg2+, Cd2+, and Pb2+. However, DMPS and DMSA prevented the inhibition caused by Cd2+ and Pb2+, but not by Hg2+. DTT did not prevent the inhibition on [3H]-glutamate binding caused by 10 μM Hg2+. In contrast, it was able to partially prevent [3H]-glutamate binding inhibition caused by 40 μM Pb2+ and Cd2+. These results demonstrated that the heavy metals present an inhibitory effect on [3H]-glutamate binding. In addition, BAL was less effective to protect [3H]-glutamate binding inhibition caused by these metals than other chelating agents studied.

Heavy metals BAL DMPS DMSA glutamate binding and neurotoxicity 


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Copyright information

© Plenum Publishing Corporation 2003

Authors and Affiliations

  • Félix Antunes Soares
    • 1
  • Marcelo Farina
    • 1
  • Francielli Weber Santos
    • 1
  • Diogo Souza
    • 1
  • João Batista Teixeira Rocha
    • 1
  • Cristina Wayne Nogueira
    • 1
  1. 1.Departamento de BioquimicaICBS, Universidade Federal doRio Grande do Sul, RSBrazil

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