Role of Calcium and Mitochondria in MeHg-Mediated Cytotoxicity

Figure 5

Schematic representation on the role of mitochondria and SER as intracellular Ca²⁺ stores and on the cellular death induced by MeHg via Ca²⁺ dyshomeostasis. (a) Under low cytosolic  [Ca²⁺]_𝑖  the SER preferentially moves Ca²⁺ from cytosol due its high affinity and low capacity to stores Ca²⁺; whereas (b) the mitochondria by presenting low affinity and high capacity to stores Ca²⁺ moves it under high cytosolic  [Ca²⁺]_𝑖; (c) the disruption of Ca²⁺ regulation produced by MeHg in either of these stores can lead to release of neuronal proapoptotic factors that may trigger cell death pathways. The scheme presented here is merely representative, and the scale of the different cellular structures does not represent the real size.

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