Fig. 4.
IL-6 and TNF-α, but not IL-4 and IL-10, increase intracellular calcium concentration and iNOS expression in human glioblastoma astrocytoma U-373 MG cells. Human glioblastoma astrocytoma U-373 MG cells were stimulated for different durations (0–75 min) with IL-6 or TNF-α (a) and IL-4 or IL-10 (b). All cytokines were tested at 10 ng/ml. Intracellular calcium and iNOS were determined by Fluo-3 fluorometric and Western blot analysis, respectively. For [Ca2+]i, values are means ± SEM; *p < 0.05 and **p < 0.01 vs matched-time controls (ANOVA and Bonferroni post-test). (c, d) Representative Western blot images of iNOS expression taken from a total of five independent experiments