The Interplay between Cyclic AMP, MAPK, and NF-κB Pathways in Response to Proinflammatory Signals in Microglia

Figure 3

TNF-α induced increases in iNOS are inhibited by the antagonism of PDE4 or NF-κB p65 in microglia. In unstimulated, resting EOC2 microglia with their morphology shown by phalloidin-488 staining ((a) green), iNOS expression was low ((b) red). Upon stimulation with TNF-α there was significant iNOS production within 3 h (d). Inhibiting PDE4 activity with Rolipram (f) or NF-κB translocation with JSH-23 (h) significantly reduced iNOS immunoreactivity in TNF-α treated microglial cells. Measurements of iNOS (red) immunoreactive (IR) signal intensity were obtained in microglia using fluorescent microscopy and Image J software for the different imaged conditions (m). Results shown are the average from three independent culture plate replicates for each treatment examined. Cell nuclei are visualized using the nuclear stain Hoechst (blue). Scale bar = 20 μm. Errors are given as SEMs. Statistical significance relative to naive controls is indicated at and versus TNF-α stimulated cells at .

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