Ultracytochemical Study of Enzyme Activities in Rat Hepatic Parenchymal Cells during the Course of Carcinogenesis Induced by 3'-methyl-4-dimethyl-aminoazobenzene (3'-MeDAB).

II. The Thiamine Pyrophosphatase Activity and the Golgi Apparatus.

Abstract

As a part of a serial study on changes of the activity of various phosphatases during the azo-dye hepato-carcinogenesis, the activity of thiamine pyrophosphatase (TPPase)was observed in the rat liver cells up to 35 weeks. From 24 weeks and after the hepatocellular hepatomas could be obtained. The TPPase activity was positive in the Golgi apparatus and membranes covering bile canaliculi in normal hepatic cells. The weak enzymatic activity was also observed occasionally in the endoplasmic reticulum.
The TPPase activity within the Golgi apparatus per se did not seem to reveal any appreciable changes in morbid cells. However the Golgi apparatus in hepatic cells in the early and intermediate stages of carcinogenesis was rather smaller than the one seen in normal parenchymal cells. The Golgi vesicles and vacuoles were diminished in number also. In some hepatocellular hepatoma, however, the Golgi apparatus was redeveloped approaching to the normal size.
Supported by grants from the Anna Fuller Fund, the Jane Coffin Childs Memorial Fund for Medical Research (Project # 196) and the Japanese Government (Gann #94157) administered by Prof. K. Ogawa.