In the present experiment, histochemical study of carbonic anhydrase was made with the use of various strain cells and following results were obtained.
1. By a slight change in the components of Haüsler's substrate a technique has been established, with which it is possible to demonstrate the localization of carbonic anhydrase in the cells.
2. The localization of carbonic anhydrase has been demonstrated in various strains cell such as HeLa cells, JTC-3 cells, and L-cells. Further, it has been found that this enzyme is localized in the nucleolus and cytoplasm in evey strain cells and the activity of the enzyme is highest in the nucleolus.
3. In the observation conducted with HeLa cells to see the effect of hormones on the enzyme activity, it has been observed that the addition of estrogen inhibits the activity carbonic anhydrase but by the further addition of progesterone the activity can be restored. However, there can be recognized no change in the enzyme activity on the addition of progesterone alone.