Figure 3.

Radioligand binding showing the specific binding of [H³]-BK (A) and [H³]-DALBK (B) to human gingival fibroblasts. Cells were pre-incubated for 24 h with either control media or media containing IL-4 (30 ng·mL⁻¹), IL-1β (100 pg·mL⁻¹) without or with IL-4 or TNF-α (25 ng·mL⁻¹) without or with IL-4. Then, the cells were challenged with radiolabelled ligands for 90 min. Values represent means ± SEM of cell bound radioactivity for four wells per group. In figures (C) and (D) is shown the increase in transient [Ca²⁺]_i concentration in response to BK (C) or DALBK (D). Human gingival fibroblasts were pre-incubated without (Ctrl) or with IL-1β (100 pg·mL⁻¹) in the absence of presence of IL-4 (30 ng·mL⁻¹) for 24 h. Then the cells were challenged with the B₁ and B₂ receptor agonists (1 μM) and intracellular calcium levels were followed by recording the fluorescence intensity. Values represent means ± SEM for 5–10 recordings. The statistically significant effects are shown by asterisks (**, P < 0.01; ***, P < 0.001).