RESUMO
A comparative study of the reproduction of an alphavirus. Venezuelan equine encephalomyelitis virus (VEE), in chick embryo fibroblasts (CEF) and oncornavirus type D (OV-D) produced spontaneously by human continuous cells (HEp-2) was carried out. The differential index of reproduction of both viruses was the yield of RNA-containing virus structures released from the cells. For VEE this index increased in the course of infection 100-150-fold. For OV-D the index changed little during long-term cultivation of the cells and was only 0.2%--1%. The effect of inhibitors, ethidium bromide and cycloheximide, on the RNA synthesis and production of virus structures was studied. Ethidium bromide was shown to inhibit reproduction of both the viruses considerably, whereas the effect of cyclohemimide on them was dissimilar: its effect on VEE virus depended on the time of its addition, while OV-D virus production did not depend on the time of its addition and was even stimulated in the presence of cycloheximide.