Biological Trace Element Research

, Volume 95, Issue 1, pp 1–10 | Cite as

Astrocyte-mediated methylmercury neurotoxicity

  • Gouri Shanker
  • Tore Syversen
  • Michael Aschner


Methylmercury (MeHg) is a potent neurotoxicant. Any source of environmental mercury represents a potential risk for human MeHg poisoning, because the methylation of inorganic mercury to MeHg in waterways results ultimately in its accumulation in the sea food chain, which represents the most prevalent source for human consumption. A small amount of MeHg accumulates in the central nervous system (CNS), particularly in astrocytes. Astrocytic swelling, excitatory amino acid (EAA) release and uptake inhibition, as well as EAA transporter expression inhibition are known sequelae of MeHg exposure. Herein, we review the effect of MeHg on additional transport systems (for cystine and cysteine) as well as arachidonic acid (AA) release and cytosolic phospholipase A2 (cPLA2) regulation and attempt to integrate the effects of MeHg in astrocytes within a mechanistic hypothesis that explains the inability of these cells to maintain control of the proper milieu of the extracellular fluid and, in turn, leads to neuronal demise.

Index Entries

Astrocytes methylmercury cystine cysteine cytosolic phospholipase A2 in vitro 


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Copyright information

© Humana Press Inc 2003

Authors and Affiliations

  • Gouri Shanker
    • 1
  • Tore Syversen
    • 3
  • Michael Aschner
    • 1
    • 2
  1. 1.Department of Physiology and PharmacologyWake Forest University School of Medicine, Medical Center BoulevardWinston-Salem
  2. 2.Interdisciplinary Program in NeuroscienceWake Forest University School of Medicine, Medical Center BoulevardWinston-Salem
  3. 3.Department of NeuroscienceNorwegian University of Science and TechnologyTrondheimNorway

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