L-Lactate dehydrogenase A chain (LDHA) is a member of the LDH/MDH superfamily and LDH family. It catalyzes the conversion of L-lactate and NAD to pyruvate and NADH in the final step of anaerobic glycolysis. LDHA is localized primarily in muscle tissue and is part of the lactate dehydrogenase family. Mutations in LDHA have been linked to exertional myoglobinuria. LDH1 is decreased in essential thrombocythemia. LDHA is induced through a non-genomic pathway of estrogen action. Reduction in LDH-A activity results in stimulation of mitochondrial respiration and decrease of mitochondrial membrane potential. Mutations in LDHA have been associated with in LDHA are the cause of glycogen storage disease type 11 (GSD11) which is a metabolic disorder that results in exertional myoglobinuria, pain, cramps and easy fatigue.