Isozyme pattern of thymidine kinase during liver regeneration.

Liver regeneration after partial hepatectomy is characterized by an active phase of cell proliferation that is associated with a marked increase in thymidine kinase activity. Using non-denaturing gel electrophoresis and different substrate specificity, two isozymes could be detected. One was identified as the adult isozyme while the other was the fetal one. Both forms were present during liver regeneration. When the regenerative process was completed, the total enzymatic activity dropped to normal values and the fetal isozyme was displaced by the adult type.