title: Absence of significant antiviral effects of beta-gamma-methylene GTP on encephalomyocarditis virus infection of L cells and mice.
abstract: The protein synthesis inhibitor beta-gamma-methylene guanosine triphosphate (Gpp-CH2p) is shown here to be ineffective as a 'leaky membrane' antiviral agent against encephalomyocarditis virus infection of L cells and mice. Studies with GppCH2p in encephalomyocarditis virus-infected L cells indicate that the cells only become permeable to the inhibitor late in infection because the compound significantly inhibits protein synthesis only when added at 4 h p.i. At this time 50 to 70% of the new infectious virus particles have already been synthesized, and this is reflected in maximum inhibition of virus yields of only about 40%. Moreover, comparison of inhibition of protein synthesis by GppCH2p in vitro and in cell cultures indicates that the intracellular concentration attained is only 0.25% of that in the medium. The lack of antiviral activity of GppCH2p in encephalomyocarditis virus-infected mice is probably due to leakiness of infected cells occurring too late for sufficient inhibition of virus synthesis to be obtained.
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D004686:Encephalomyocarditis virus / Q000187:drug effects*; D004769:Enterovirus Infections / Q000188:drug therapy*; D006160:Guanosine Triphosphate / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D007739:L Cells; D051379:Mice; D014176:Protein Biosynthesis; D013997:Time Factors
chemical_list: D006160:Guanosine Triphosphate