1959 Volume 9 Issue 2 Pages 157-164
Studies on the site of action of various antivirals including caprochlorone, chartreusin, 2, 5-dimethyl-benzimidazole, 5, 6-dichlor-1-b-ribofuranosyl-benzimidazole, myxoviromycin, canavanine sulfate and dinitrophenol were conducted against PR8 virus growth in chorioallantoic membrane and Sendai virus growth in L cells.
Firstly, these antivirals were tested against the growth of PR8 virus in a tissue culture system, consisting of 2.0ml of Hanks'solution and 4 pieces of chorioallantoic membrane together with the attached shell.
The results obtained in the system are as follows:
1) These antivirals in fairly high concentrations did not show any inhibitory tendency of viral hemagglutination. They were not virocidal and their inhibitory effect on the adsorption stage was also excluded as far as tested with 2 or more times of minimum inhibitory concentrations. Thus the inhibition of virus synthesis within the cell was suggested as the site of antiviral activities.
2) Determining the sensitive stage of the virus growth to these antivirals, chartreusin, 2, 5-dimethyl-benzimidazole and 5, 6-dichlor-1-b-ribofuranosyl-benzimidazole were grouped as an early active agent, and caprochlorone, canavanine sulfate, dinitrophenol and myxoviromycin were grouped as the late active antivirals. In other words, latter antivirals were active even when added at late stage of the incubation.
3) On the basis of calculating chemotherapeutic index, myxoviromycin was thought to be the best among these antivirals.
Secondly, these antivirals were examined their effect on the growth of Sendai virus in Earle's L cells.
The results obtained in the system may be summarized as follows:
1) All these antivirals showed the toxicity to L cells and the concentration which inhibited the growth of virus was around the vicinities of their toxic concentrations.
2) Both myxoviromycin and caprochlorone inhibited the cytopathogenic effect of the Sendai virus in addition to the inhibition of hemagglutinin production at critical concentrations. With other antivirals tested here, cytopathogenic effect of the virus was not affected even when the hemagglutinin production was impaired.
3) Myxoviromycin, in a wide range of concentration, showed the toxicity of low grade and within this range, the antibiotic inhibited the growth of the Sendai virus.
