title: [Isoenzyme system of lactate dehydrogenase in human cells and tissues].
abstract: Comparative investigation of total activity and molar ratio of M-polypeptide chains (MM) of lactate dehydrogenase in diploid human cells with normal karyotype is carried out. It is found that the activity values in the passages studied (from 8 to 22) varies considerably, the variation coefficient Wn being 47.5%. Molar ratio of M-polypeptide chains of lactate dehydrogenase turned to be more stable (Wn=9.1%). Comparison of cell lines from different tissues and of respective initial tissues for MM values has revealed an increase of the content of lactate dehydrogenase M-polypeptide chains in embryonic cell lines with respect to initial tissues. Nevertheless, reliable differences in MM values between some cell lines of different tissue origin retain through 9--20 passages. A mechanism of lactate dehydrogenase biosynthesis and a system controlling the ratio of its subunits are discussed.
mesh_terms: D002460:Cell Line; D006801:Humans; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase / Q000378:metabolism*
chemical_list: D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase
vernacular_title: Izofermentnaia sistema laktatdegidrogenazy v kul'tinviruemykh i tkaniakh cheloveka.