5′-Nucleotidase

Summary 5′-Nucleotidase and alkaline phosphatase activity was investigated in the developing kidney of the mouse by histochemical and electrophoretic methods. The growth of the kidneys was studied by determining the incorporation of radioactive thymidine by autoradiography. During development the isoenzyme patterns of 5′-nucleotidase and alkaline phosphatase behaved in a different way. In correlating the histochemical and electrophoretic changes, it has been found that the 5′-nucleotidase isoenzymes as well as the alkaline phosphatase isoenzymes are located in different parts of the kidney. In the convoluted part of the proximal tubule 5′-nucleotidase isoenzyme 3 and alkaline phosphatase isoenzyme 5 are present, while in the straight part of this tubule 5′-nucleotidase isoenzyme 5 and — upto three weeks — alkaline phosphatase isoenzyme 3 are located. So in tissue structures having different functional capacities, different isoenzymes of 5′-nucleotidase and alkaline phosphatase are found.