1980 Volume 76 Issue 7 Pages 609-619
The potency of anti-inflammatory and ulcerogenic activities of a new anti-inflammatory agent, (10-methyl-7-methoxy-2-phenothiazinyl)-2-propionic acid (protizinic acid, PRT), was compared with those of various known non-steroidal anti-inflammatory agents in 5 experimental models. The ED30 of PRT in carrageenin edema with oral administration was 18.0 mg/kg and its potency was third following indomethacin (IM) and diclofenac sodium (DF), among the 15 agents tested. The ED50 of PRT in ultraviolet erythema with oral administration and the IC50 in protein denaturation were 1.07 mg/kg and 0.89×10-5M, respectively and the activities were the most potent among all agents. The IC50 of PRT in platelet aggregation induced by arachidonic acid was 5.55×10-5M and the rank of potency was sixth following to IM, DF, flufenamic acid, aluminium flufenamate and mefenamic acid (MF). Furthermore, the ED50 of PRT in ulcerogenic activity was 52.3 mg/kg and ranked fifth following azapropazone, MF, alclofenac, metiazinic acid (MA), except for basic agents, mepirizole, benzydamine hydrochloride and tiaramide hydrochloride. Thus, PRT seemed to have a relatively weak ulcerogenic activity in contrast to potent anti-inflammatory activity. Also, PRT was superior to MA, an analogue of PRT, in potency of anti-inflammatory activity, in all experimental models.
