| Affiliation: | (1) Department of Tropical Medicine, Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan;(2) Department of Tropical Medicine and Parasitology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan |
| Abstract: | The effect of five different cytochalasins on the growth, encystation and excystation of Entamoeba invadens was examined. At 10  M, cytochalasins B, D, E and dihydrocytochalasin B markedly inhibited growth. Encystation was inhibited by cytochalasin D at 1 M but not by other cytochalasins at the same concentration, whereas it was inhibited by 10 M of cytochalasins B, E and dihydrocytochalasin B as well as cytochalasin D. Excystation, which was assessed by counting the number of metacystic amoebae after inducing excystation, was markedly enhanced by cytochalasin D as previously demonstrated, whereas the enhancing effect of cytochalasins A, B and dihydrocytochalasin B was weak. In contrast, cytochalasin E at 10 M inhibited excystation and metacystic development. These results indicate that there is a difference in the effect of different cytochalasins on the growth and differentiation of E. invadens, depending on differences in their chemical structure. |
