Figure 4. Hyperglycemia induces [Ca²⁺]i-dependent and CaMKll-dependent JNK phosphorylation and Fas protein expression in RF/6A cells. RF/6A cells were incubated for 96 h in serum-free medium containing 5.5 glucose (NG), 30 mM glucose (HG), or HG plus 2-APB, KN93, or SP600125 as indicated, and subjected to western blotting analysis for A: JNK, and p-JNK and for B: Fas. β-actin served as the loading control. JNK, p-JNK, and Fas levels were quantified by densitometry analysis in each treatment group (right panels). Bars represented mean±SD from at least three independent experiments with seven cells per treatment group. * p<0.05 versus NG; ^# p<0.05 versus HG; ^# p<0.05 versus NG.