Fig. 6

Extracellular ATP causes release of IL-1β from purified rat cerebellar microglia primed with Apo-SAA or LPS. Microglia cultured in 96-well plates were first incubated 2 h with 0.5 μg/ml recombinant human Apo-SAA (a) or 0.1 μg/ml LPS (b). ATP was then added to a final concentration of 5 mM. After a further 60-min incubation, culture medium (‘extra’) and cell lysates (‘intra’) were collected for IL-1β analysis by ELISA. As for cortical microglia, here also Apo-SAA was a more efficacious stimulus than was LPS (note the difference in y-axis scales). Control (CTRL). Data are mean ± sem (n = 6). ***p < 0.001: Apo-SAA vs Apo-SAA + ATP; or LPS vs LPS + ATP (extracellular). °°°p < 0.001 vs Apo-SAA vs Apo-SAA + ATP; or LPS vs LPS + ATP (intracellular)