Description
Functional lactate dehydrogenase are homo or hetero tetramers composed of M and H protein subunits encoded by the LDHA and LDHB genes, respectively. The major isozymes of skeletal muscle and liver has four muscle (M) subunits; while the main isozymes for heart muscle contains four (H) subunits. The other variants contain both types of subunits. Elevated levels of LDH indicate tissue breakdown in hemolysis. LDH can be used as a marker of myocardial infarction, peaking at days 3 and lasting through day 10. Other disorders indicated by elevated LDH include cancer, meningitis, encephalitis, acute pancreatitis, and HIV. Defects in LDHB are a cause of hereditary LDHB deficiency; however LDHB deficiency is usually asymptomatic