Yes, LDH exists in multiple isoforms, which are tissue-specific. In humans, there are five isoenzymes (LDH-1 to LDH-5), each composed of different combinations of two subunits: H (heart) and M (muscle). These isoforms exhibit different kinetic properties and affinities for substrates, allowing them to cater to the metabolic needs of different tissues. For instance, LDH-1 is prevalent in the heart and is more efficient at converting lactate to pyruvate, facilitating oxidative metabolism.
