Correlation between antagonizing effects of RU486 and endogenous cortisol. The levels of cortisol were measured in the serum of 11 healthy donors. In these donors whole-blood cultures were performed as described in Fig 1. The effect of 50 μmol/L RU486 was studied on IL-10 and IL-12(p40) production. The level of cortisol in the serum of each donor is plotted against the effect of RU486 on the IL-10 (bottom) and IL-12(p40) (top) production. The effect of RU486 is expressed as the percentage of the initial response with LPS in each donor. Each symbol represents one individual donor. The blood was collected between 8 and 10 am and put into culture immediately after collection.