Dissociation between antiinflammatory action of tilorone and its interferon inducing activity.

A relation between antiinflammatory action of tilorone and its interferon inducing activity was studied in rats. Tilorone (20-100 mg/kg, p.o.) was dose-dependently effective on both carrageenin oedema and passive Arthus, suggesting that the pharmacological property of the compound is different from nonsteroidal antiinflammatory medicaments which were weak inhibitors of passive Arthus. The antiinflammatory action of tilorone had a time-lag and priming with tilorone 24 hrs prior to inflammatory insult was required to demonstrate maximal efficacy. This time course change was similar to that of serum interferon level. In addition, a high correlation was observed between the antiinflammatory activity and the serum interferon level. However, the antiinflammatory action was scarcely affected even if the serum interferon level was remarkably lowered by treatment of an inhibitor of protein biosynthesis, cycloheximide. These findings suggested that the antiinflammatory action of tilorone could be dissociated from its interferon inducing activity.