Incubation of J774A.1 or THP-1 macrophages with drugs except the highest concentration of troglitazone does not lead to the release of IL-1ß, but incubation of these cells with supernatants from incubations of hepatocytes with troglitazone, tolcapone, or entacapone does. (A) J774A.1 cells treated with troglitazone or pioglitazone directly, or with hepatocyte supernatant from hepatocytes previously treated with troglitazone or pioglitazone. (B) THP-1 cells treated with troglitazone or pioglitazone directly, or with hepatocyte supernatant from hepatocytes previously treated with troglitazone or pioglitazone. (C) J774A.1 cells with tolcapone or entacapone directly, or with hepatocyte supernatant from hepatocytes previously treated with tolcapone or entacapone. (D) THP-1 cells treated with tolcapone or entacapone directly, or with hepatocyte supernatant from hepatocytes previously treated with tolcapone or entacapone. Values represent the mean ± SE. Analyzed for statistical significance by 1-way ANOVA. p < .05 was considered significant (*p < .05; **p < .01).