ELECTRON-MICROSCOPIC STUDIES ON EXPERIMENTAL POISONING IN MICE INDUCED BY CYLINDROSPERMOPSIN ISOLATED FROM BLUE-GREEN-ALGA UMEZAKIA NATANS

The effects of cylindrospermopsin isolated from a blue-green alga Umez akia natans on mice were examined morphologically and biochemically. T he main target of the phycotoxin was the liver. The thymus, kidneys an d heart were also affected. There were four consecutive phases of the pathological changes in the liver. The initial phase was that of inhib ition of the protein synthesis, the second phase of membrane prolifera tion followed, and then the third phase of fat droplet accumulation an d finally the phase of cell death. Using globin synthesis in the rabbi t reticulocytes system, it was clearly demonstrated that cylindrosperm opsin is a potent inhibitor of the protein synthesis. Protein in micro somes from the mouse livers treated by cylindrospermopsin decreased in amount more significantly than that of phospholipid in microsomes. Fu rthermore, the amount of total P450 was extensively diminished in the toxin treated with hepatic microsomes.