Effect of propranolol (Pro) and atenolol (Ate) on the enhancing effect of epinephrine (Epi) on production of IL-6 (A), IL-8 (B), and IL-13 (C) from IL-1β-induced HMC-1 cells. To each well of a 6 well culture plate, two ml of HMC-1 mast cells (0.75 × 106 cells/ml) were cultured alone (Medium), or in the presence of IL-1β (10 ng/ml), Epi (1 × 10-5 M), Pro (1 × 10-4 to 1 × 10-6 M), Ate (1 × 10-4 to 1 × 10-6 M), and the combinations of these reagents for 24 hrs in triplicate. Supernatants were harvested for measuring IL-6, IL-8, and IL-13 by ELISA. IL-8 and IL-13 production were not detected in the Medium, Epi, Pro, and Ate alone groups. In A and B, by Student's t-test analysis, * and + indicate p < 0.05, when compared with the IL-1β-treated group, and the IL-1β plus Epi group, respectively. In C, * indicates p < 0.01, when compared with the IL-1β-treated group; p values for ++, +, ##, and # were <0.00005, <0.0005, <0.01, and <0.05, when compared with the IL-1β plus Epi group.