Systemic interleukin I administration suppresses arachidonic acid-induced ear oedema in the mouse

Recombinant human interleukin 1 beta (IL-1 beta), given intraperitoneally to mice as a single injection, significantly suppressed the development of arachidonic acid (AA)-induced ear oedema. This effect was noted 2 h after administration and for at least 5 days afterwards. IL-1 beta was effective in the dose range of 250 ng-20 micrograms/mouse. Injection of IL-1 beta per se resulted in erythema of the ears, and thus, IL-1 beta has the capacity not only to induce and augment but also to suppress inflammatory responses. Indomethacin administered as subcutaneously-implanted pellets did not influence the IL-1 beta induced-ear erythema, but suppressed to some extent the effect of IL-1 beta on the AA-induced ear oedema.