ATP Is Required and Advances Cytokine-Induced Gap Junction Formation in Microglia In Vitro
Figure 1
ATP advances the onset of TNF-α/IFN-γ-induced dye coupling. (a)–(d) Dye transfer was evaluated 2 min after Lucifer yellow (LY) microinjection in a single cell (indicated with an asterisk). Representative pictures of LY transfer in rat microglia (a), (c) or EOC20 cells (b), (d) under control condition or after TNF-α plus ATP (TNF-α/ATP) treatment for 3.5 h, as indicated. Phase contrasts of each micrograph are shown at the right panels. Scale bar: 20 μm. (e) Time course of the incidence of dye coupling (IDC) as percentage of IDC in EOC20 cells under control conditions (dashed line) or after treatment with TNF-α plus ATP (black circles), TNF-α/IFN-γ plus ATP (white triangles), or TNF-α/IFN-γ (black diamonds). Each point corresponds to the mean of 3 independent experiments. (f) Graph showing the maximum values of IDC after treatment with TNF-α plus ATP for 3.5 h, TNF-α/IFN-γ plus ATP for 5 h, or TNF-α/IFN-γ for 9 h. versus control condition. Each bar represents the mean ± SEM, . No significant differences were observed when comparing microglia and EOC20 cells responses to different treatment in dye transfer assays. Concentrations: 1 ng/mL TNF-α; 1 mM ATP; 1 ng/mL IFN-γ.
