Effect of corticosteroids on arachidonate induced mortality in male and female mice.

Sodium arachidonate (50 mg/kg) given intravenously to male and female mice induces pulmonary emboli followed by respiratory distress and cyanosis. Female mice are significantly more resistant to this treatment than male mice. Cortisone pretreatment for four days to intact mice (10 mg/kg/day/4 days) had a significant protective effect in both males and females against arachidonate toxicity, eliminating the sex difference previously observed. Adrenalectomy four days before arachidonate infusion increased the sensitivity to SA and resulted in 100% mortality in both sexes. Pretreatment of adrenalized animals with cortisone significantly reduced to some degree the mortality rate in both sexes. Castration of male and female mice three weeks before adrenalectomy did not affect the mortality rate seen following adrenalectomy alone. In conclusion, exogenous cortical steroids augment the resistance of even intact mice and are absolutely necessary for survival in adrenalectomized animals. The observed sex differences in untreated intact animals is not seen after treatment with cortisone or adrenalectomy.