[Effects of MY-5116 on experimental animal models of type I-type IV allergic reactions and the formation of IgE antibody].

The effects of a new anti-allergic agent, MY-5116: isoamyl 5,6-dihydro-7,8-dimethyl-4,5-dioxo-4H-pyrano [3,2-c] quinoline-2-carboxylate, on experimental animal models of type I approximately type IV allergic reactions and the formation of IgE antibody were investigated. MY-5116 administered intraperitoneally at doses of 30 and 100 mg/kg suppressed significantly the homologous PCA in guinea pigs. MY-5116 administered intraperitoneally at the dose of 100 mg/kg also suppressed significantly the heterologous PCA in guinea pigs. MY-1250, the main active metabolite of MY-5116, showed no suppression on the Schultz-Dale reaction in guinea pigs, and MY-5116 showed no inhibition on the active systemic anaphylaxis in mice (type I). MY-5116 showed no inhibition on the reversed cutaneous anaphylaxis in rats (type II), the Forssman reaction in guinea pigs (type II), the Arthus reaction in mice (type III) and the delayed type hypersensitivity in mice (type IV). MY-5116 showed no suppression on the formation of IgE antibody in C3H/He and BALB/c mice and rats. From these results, it is concluded that MY-5116 selectively suppresses the experimental models of type I allergic reaction.