FIGURE 2.

Illustration of mitochondrial calcium transport. Mitochondrial associated membranes (MAMs) result in microdomains of high Ca²⁺ levels that facilitate Ca²⁺ entry through the outer mitochondrial membrane via voltage dependent anion channel (VDAC). Ca²⁺ crosses the inner mitochondrial membrane via the mitochondrial uniporter (MCU), which then stimulates respiration via increases in citric acid cycle enzymes. Ca²⁺ is extruded from the mitochondria via Na⁺/Ca²⁺ exchanger (NCX) and H⁺/Ca²⁺ exchanger (HCX) in the inner membrane and the outer membrane via the mitochondrial permeability transition pore (mPTP).