Fatty Acids in Energy Metabolism of the Central Nervous System

Figure 6

The malate-aspartate shuttle (MAS). The mitochondrial inner membrane is impermeable for NADH. In order to effectively utilize lactate for mitochondrial respiration, lactate must be converted to pyruvate in the reaction lactate + NAD⁺→ pyruvate + NADH. NADH is reoxidized by the MAS. The process is unidirectional because GAT (aralar) is electrogenic and the matrix NADH is rapidly oxidized by the respiratory chain.