[Effect of virulent and anttenuated variants of viruses of American equine encephalomyelitis on the mitotic activity of the cells].

A comparative study of reproduction of Venezuelan and Eastern equine encephalomyelitis (VEE and EEE) viruses in L cell culture showed the disorders of the mitotic activity of the infected cultures to depend on the variant of the inoculated virus and the degree of its attenuation. The highest number of pathological mitosis was observed within 12--24 hours after inoculation of the cultures, the attenuated variants of both the viruses causing lower numbers of pathological mitoses than virulent variants. EEE virus was found to induce accumulation of pyknotized nuclei in the stage of telophase in the culture.