<prompt> LDH isoenzyme specific for heart is -LDH1LDH2LDH3LDH4  <response>: Ans. is a i.e., LDH1 Lactate Dehydrogenase converts pyruvate to lactate. It is present in cytoplasm of cells It is a tetramer. Two subunits H and M in various combinations make up the various isoenzymes of LDHLDH ISOENZYMESUBUNITSLOCATIONLDH 1H4Heart, RBC, BrainLDH 2H3M1Reticuloendothelial cellsLDH3H2M2LungsLDH4H1M3Kidneys, placenta, PancreasLDH 5M4Liver and skeletal muscle In blood generally LDH 2 isoenzyme concentration is higher. In myocardial infarction, LDH1 concentration is increased. This LDH 1 being more than LDH2 is called as flipped pattern of LDH which is suggestive of myocardial infarction. 