Fig. A schematic model of some of the currently proposed mechanism for cellular damage induced by MeHg in the CNS. In the extracellular
environment, MeHg inhibits glutamate uptake, as well as a number of the amino acids that are associated with the synthesis of astrocytic
glutathione (GSH). Accumulation of glutamate in the extracellular space and the resulting excessive activation of NMDA receptors can
result in excitotoxicity, and, ultimately, cell death. Other proposed mechanisms are related with mitochondrial MeHg -associated dysfunction,
including impaired cytoplasmatic Ca
2+
homeostasis and release of ROS, metabolic inhibition that leads to impaired ATP production, lipidic
peroxidation and nuclear damage. MeHg also can provoke microtubules chain disruption decreasing vesicular migration or genotoxicity