PURIFICATION AND IMMUNOHISTOCHEMICAL STUDY OF SORBITOL DEHYDROGENASE IN RAT LIVER

Abstract

Sorbitol dehydrogenase was purified from rat liver and showed a single line during disc electrophoresis. The substrate specificity of the purified enzyme was very low; the Km value of the enzyme was 4.5 .times. 10-4 M for sorbitol, 2.6 .times. 10-4 M for xylitol and 2.4 .times. 10-3 M for ribitol, respectively. The localization of sorbitol dehydrogenase was investigated using both fluorescein-labeled and peroxidase-labeled antibody methods on the light microscopic level. The antigen was recognized concentratedly around the nucleus and in lower amounts in the other parts of the cytoplasm of the liver cells in a granular profile. In the EM study using the peroxidase-labled antibody technique, the positive deposits were observed in the reticulated or net-like pattern in the amorphous part of the cytoplasm of parenchymal cells, which might correspond to the glycogen area.