It was shown that although the first inoculation of even a small amount of endotoxin during intravenous epinephrine infusion precipitates shock, by inhibiting the epinephrine removing capacity, after repeated endotoxin pretreatment a marked resistance to epinephrine infusion can be induced by virtue of a pronounced adaptation of the epinephrine removing capacity. This enhancement of the epinephrine removing capacity in the endotoxin-tolerant state was observed even in the absence of glucocorticoid which is also able to induce it. It was discussed that some of the effects of glucocorticoid can be realized in the adaptation to endotoxin conditioning. This would shed a new light upon the problem of cross-resistance of endotoxin-tolerant animals to other stresses not concerned with bacterial endotoxin.