Toxicity of Microcystis aeruginosa K-139 strain.

Toxicity of the cells of a newly established axenic Microcystis aeruginosa K-139 strain to mice was studied. LD50 of the cells harvested in the mid-log phase was 7.3 mg/kg. The organs of acute dead mice were examined histopathologically. The blood congestion and necrosis of the parenchymal cells around the central veins in the liver were observed, but other organs seemed to be normal. The liver damage was confirmed by the tests of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) activities in the sera of the mice after the injection with the K-139 cells. Furthermore, the K-139 cells were capable of inducing interleukin 1 (IL-1) production by peritoneal macrophages in vitro.